feat(schema): add Classroom and RoomUnit classes for classroom_count migration

- Create Classroom.yaml (subclass of Facility)
- Create RoomUnit.yaml (subclass of Unit for room counting)
- Create RoomUnitTypeEnum.yaml with room type values
- Update EducationCenter.yaml to use has_or_had_facility with Classroom
- Archive classroom_count.yaml slot

Rule 53 compliance: Replaces simple integer count with structured facility model.

frontend/public/schemas/20251121/linkml/manifest.json

@@ -1,5 +1,5 @@
 {
-  "generated": "2026-01-19T12:05:24.104Z",
+  "generated": "2026-01-19T12:05:53.461Z",
   "schemaRoot": "/schemas/20251121/linkml",
   "totalFiles": 2969,
   "categoryCounts": {

schemas/20251121/linkml/manifest.json

@@ -1,5 +1,5 @@
 {
-  "generated": "2026-01-19T12:05:53.461Z",
+  "generated": "2026-01-19T12:10:38.542Z",
   "schemaRoot": "/schemas/20251121/linkml",
   "totalFiles": 2969,
   "categoryCounts": {

schemas/20251121/linkml/modules/classes/Classroom.yaml

@@ -0,0 +1,139 @@
+# Classroom - Classroom facility class
+#
+# Created per slot_fixes.yaml migration for: classroom_count
+# Creation date: 2026-01-19
+#
+# Rule 53 (No Bespoke Slots): classroom_count → has_or_had_facility + Classroom
+# Rule 39 (RiC-O Naming): Uses has_or_had_* pattern
+
+id: https://nde.nl/ontology/hc/class/Classroom
+name: Classroom
+title: Classroom Facility
+
+prefixes:
+  linkml: https://w3id.org/linkml/
+  hc: https://nde.nl/ontology/hc/
+  schema: http://schema.org/
+  qudt: http://qudt.org/schema/qudt/
+
+default_prefix: hc
+
+imports:
+  - linkml:types
+  - ./Facility
+  - ./Quantity
+  - ./RoomUnit
+  - ../slots/has_or_had_quantity
+  - ../slots/has_or_had_unit
+
+classes:
+  Classroom:
+    is_a: Facility
+    class_uri: schema:Classroom
+    description: |
+      A classroom facility at an education center or heritage institution.
+      
+      **RULE 53 MIGRATION**:
+      Replaces the simple `classroom_count` integer slot with a richer facility model:
+      - `has_or_had_quantity` → number of classroom spaces
+      - `has_or_had_unit` → RoomUnit (specifies what is being counted)
+      
+      **USAGE**:
+      ```yaml
+      has_or_had_facility:
+        - facility_name: "Classroom Wing"
+          has_or_had_quantity:
+            numeric_value: 4
+          has_or_had_unit:
+            unit_type: CLASSROOM
+      ```
+      
+      **CHARACTERISTICS**:
+      - Dedicated teaching/learning space
+      - Capacity for group instruction
+      - May include AV equipment
+      - Configurable seating arrangements
+      
+    slots:
+      - has_or_had_quantity
+      - has_or_had_unit
+    
+    slot_usage:
+      has_or_had_quantity:
+        range: Quantity
+        inlined: true
+        description: |
+          Number of classroom spaces in this facility.
+        examples:
+          - value: |
+              numeric_value: 4
+            description: 4 classroom spaces
+      
+      has_or_had_unit:
+        range: RoomUnit
+        inlined: true
+        description: |
+          Unit specification for the count (classroom, seat, etc.).
+        examples:
+          - value: |
+              unit_type: CLASSROOM
+            description: Counting classrooms
+    
+    attributes:
+      seating_capacity:
+        range: integer
+        description: Total seating capacity across all classrooms
+      
+      av_equipped:
+        range: boolean
+        description: Whether classrooms have AV equipment
+      
+      flexible_seating:
+        range: boolean
+        description: Whether seating can be reconfigured
+    
+    exact_mappings:
+      - schema:Classroom
+    
+    close_mappings:
+      - schema:Room
+      - schema:Place
+    
+    annotations:
+      specificity_score: "0.55"
+      specificity_rationale: "Moderately specific - classrooms common in education centers."
+      template_specificity:
+        archive_search: 0.30
+        museum_search: 0.50
+        library_search: 0.45
+        collection_discovery: 0.20
+        person_research: 0.15
+        location_browse: 0.60
+        identifier_lookup: 0.10
+        organizational_change: 0.25
+        digital_platform: 0.15
+        general_heritage: 0.55
+    
+    examples:
+      - value:
+          facility_name: "Education Wing Classrooms"
+          facility_description: "Four fully-equipped classroom spaces for educational programs"
+          has_or_had_quantity:
+            numeric_value: 4
+          has_or_had_unit:
+            unit_type: CLASSROOM
+          seating_capacity: 120
+          av_equipped: true
+          flexible_seating: true
+        description: Museum education center classroom facility
+      
+      - value:
+          facility_name: "Archive Learning Rooms"
+          facility_description: "Two seminar rooms for genealogy and research workshops"
+          has_or_had_quantity:
+            numeric_value: 2
+          has_or_had_unit:
+            unit_type: CLASSROOM
+          seating_capacity: 40
+          av_equipped: true
+        description: Archive education classroom facility

schemas/20251121/linkml/modules/classes/EducationCenter.yaml

@@ -11,7 +11,11 @@ imports:
   # REMOVED 2026-01-15: ../slots/annual_participants - migrated to has_or_had_annual_participant_count
   # REMOVED 2026-01-15: ../slots/booking_required - migrated to is_or_was_required
   - ../slots/is_or_was_required
-  - ../slots/classroom_count
+  # REMOVED 2026-01-19: ../slots/classroom_count - migrated to has_or_had_facility with Classroom
+  - ../slots/has_or_had_facility
+  - ./Classroom
+  - ./RoomUnit
+  - ../enums/RoomUnitTypeEnum
   - ../slots/has_or_had_custodian_type
   # Shared slots (replacing education_center_* slots per Rule 53)
   - ../slots/has_or_had_identifier
@@ -94,7 +98,8 @@ classes:
     - has_or_had_annual_participant_count
     # REMOVED 2026-01-15: booking_required - migrated to is_or_was_required
     - is_or_was_required
-    - classroom_count
+    # REMOVED 2026-01-19: classroom_count - migrated to has_or_had_facility with Classroom
+    - has_or_had_facility
     - has_or_had_custodian_type
     # MIGRATED 2026-01-15: education_center_* slots replaced with shared slots per Rule 53
     - has_or_had_identifier  # was: education_center_id
@@ -184,11 +189,31 @@ classes:
           description: Professional development
         - value: Genealogy workshops
           description: Specialized workshops
-      classroom_count:
+      # REMOVED 2026-01-19: classroom_count - migrated to has_or_had_facility with Classroom
-        range: integer
+      # classroom_count:
+      #   range: integer
+      #   examples:
+      #   - value: 4
+      #     description: 4 classrooms
+      has_or_had_facility:
+        range: Classroom
+        inlined: true
+        multivalued: true
+        description: |
+          Classroom facilities at this education center.
+          MIGRATED 2026-01-19: Replaces classroom_count slot per Rule 53.
+          Uses Classroom class (subclass of Facility) with has_or_had_quantity
+          and has_or_had_unit for structured room counting.
         examples:
-        - value: 4
+        - value: |
-          description: 4 classrooms
+            facility_name: "Main Classroom Wing"
+            has_or_had_quantity:
+              numeric_value: 4
+            has_or_had_unit:
+              unit_type: CLASSROOM
+            seating_capacity: 120
+            av_equipped: true
+          description: 4 classroom facility
       # REMOVED 2026-01-14: workshop_space - migrated to has_or_had_quantity with Quantity
       # workshop_space:
       #   range: integer
@@ -291,7 +316,16 @@ classes:
         - Interactive workshops
         - Family treasure hunts
         - Teacher training days
-        classroom_count: 4
+        # MIGRATED 2026-01-19: classroom_count → has_or_had_facility + Classroom
+        has_or_had_facility:
+        - facility_name: "Education Wing Classrooms"
+          has_or_had_quantity:
+            numeric_value: 4
+          has_or_had_unit:
+            unit_type: CLASSROOM
+          seating_capacity: 120
+          av_equipped: true
+          flexible_seating: true
         has_or_had_quantity:
           value: 2
           unit: workshop_spaces
@@ -322,7 +356,15 @@ classes:
         - Genealogy workshops
         - Paleography basics
         - Teacher curriculum support
-        classroom_count: 2
+        # MIGRATED 2026-01-19: classroom_count → has_or_had_facility + Classroom
+        has_or_had_facility:
+        - facility_name: "Learning Rooms"
+          has_or_had_quantity:
+            numeric_value: 2
+          has_or_had_unit:
+            unit_type: CLASSROOM
+          seating_capacity: 40
+          av_equipped: true
         max_group_size: 20
         has_av_equipment: true
         is_or_was_required: true

schemas/20251121/linkml/modules/classes/RoomUnit.yaml

@@ -0,0 +1,113 @@
+# RoomUnit - Unit class for counting room/space facilities
+#
+# Created per slot_fixes.yaml migration for: classroom_count
+# Creation date: 2026-01-19
+#
+# Rule 53 (No Bespoke Slots): classroom_count → has_or_had_facility + Classroom + RoomUnit
+# Rule 39 (RiC-O Naming): Uses has_or_had_* pattern
+
+id: https://nde.nl/ontology/hc/class/RoomUnit
+name: RoomUnit
+title: Room Unit
+
+prefixes:
+  linkml: https://w3id.org/linkml/
+  hc: https://nde.nl/ontology/hc/
+  qudt: http://qudt.org/schema/qudt/
+  schema: http://schema.org/
+
+default_prefix: hc
+
+imports:
+  - linkml:types
+  - ./Unit
+  - ../enums/RoomUnitTypeEnum
+
+classes:
+  RoomUnit:
+    is_a: Unit
+    class_uri: hc:RoomUnit
+    description: |
+      A unit of measurement for counting rooms or spaces in a facility.
+      
+      **RULE 53 MIGRATION**:
+      Replaces simple integer count slots with typed unit specification:
+      - `classroom_count: 4` → `has_or_had_quantity: 4` + `has_or_had_unit: {unit_type: CLASSROOM}`
+      
+      **ROOM TYPES**:
+      - CLASSROOM - Teaching/learning spaces
+      - WORKSHOP_SPACE - Hands-on activity areas
+      - SEMINAR_ROOM - Discussion/presentation spaces
+      - LABORATORY - Scientific/conservation labs
+      - STUDIO - Creative/production spaces
+      - READING_ROOM - Research/study areas
+      - STORAGE_ROOM - Collection storage spaces
+      - OFFICE - Administrative spaces
+      
+      **USAGE PATTERN**:
+      ```yaml
+      has_or_had_facility:
+        - facility_name: "Education Wing"
+          has_or_had_quantity:
+            numeric_value: 4
+          has_or_had_unit:
+            unit_type: CLASSROOM
+      ```
+      
+    exact_mappings:
+      - qudt:Unit
+    
+    close_mappings:
+      - schema:Room
+    
+    attributes:
+      unit_type:
+        range: RoomUnitTypeEnum
+        required: true
+        description: |
+          The type of room/space being counted.
+        examples:
+          - value: CLASSROOM
+            description: Classroom space
+          - value: READING_ROOM
+            description: Reading room
+    
+    annotations:
+      custodian_types: '["E", "L", "A", "M", "R"]'
+      custodian_types_rationale: >-
+        Room counting most relevant for education providers (E), libraries (L),
+        archives (A), museums (M), and research centers (R).
+      custodian_types_primary: "E"
+      specificity_score: 0.45
+      specificity_rationale: >-
+        Moderately specific - room counting common in education/facility contexts.
+      template_specificity:
+        archive_search: 0.35
+        museum_search: 0.45
+        library_search: 0.50
+        collection_discovery: 0.20
+        person_research: 0.10
+        location_browse: 0.55
+        identifier_lookup: 0.10
+        organizational_change: 0.20
+        digital_platform: 0.10
+        general_heritage: 0.45
+    
+    examples:
+      - value:
+          unit_type: CLASSROOM
+        description: Unit for counting classroom spaces
+      
+      - value:
+          unit_type: READING_ROOM
+        description: Unit for counting reading rooms
+      
+      - value:
+          unit_type: WORKSHOP_SPACE
+        description: Unit for counting workshop areas
+    
+    comments:
+      - Created from slot_fixes.yaml migration (2026-01-19)
+      - Specialized unit for room/space counting
+      - Subclass of Unit with room-specific type enum
+      - Used with Classroom and similar facility classes

schemas/20251121/linkml/modules/enums/RoomUnitTypeEnum.yaml

@@ -0,0 +1,134 @@
+# RoomUnitTypeEnum - Types of rooms/spaces for counting
+#
+# Created per slot_fixes.yaml migration for: classroom_count
+# Creation date: 2026-01-19
+#
+# Rule 53 (No Bespoke Slots): Supports RoomUnit class for facility counting
+
+id: https://nde.nl/ontology/hc/enum/RoomUnitTypeEnum
+name: room_unit_type_enum
+title: Room Unit Type Enum
+description: >-
+  Enumeration of room and space types for counting facilities.
+  
+  **RULE 53 COMPLIANT**: Supports RoomUnit class for standardized
+  room counting in heritage facility metrics.
+
+prefixes:
+  linkml: https://w3id.org/linkml/
+  hc: https://nde.nl/ontology/hc/
+  schema: http://schema.org/
+
+imports:
+  - linkml:types
+
+default_prefix: hc
+
+enums:
+  RoomUnitTypeEnum:
+    description: >-
+      Standard room types for counting heritage facility spaces.
+      
+      Used with RoomUnit class in has_or_had_unit slot for facility counting.
+    permissible_values:
+      # Educational spaces
+      CLASSROOM:
+        description: Teaching/learning space for group instruction
+        meaning: schema:Classroom
+        annotations:
+          usage_context: education
+          typical_capacity: "20-40"
+      
+      WORKSHOP_SPACE:
+        description: Hands-on activity area for practical work
+        annotations:
+          usage_context: education
+          typical_capacity: "10-20"
+      
+      SEMINAR_ROOM:
+        description: Discussion/presentation space for smaller groups
+        annotations:
+          usage_context: education
+          typical_capacity: "10-25"
+      
+      LECTURE_HALL:
+        description: Large presentation space for lectures
+        annotations:
+          usage_context: education
+          typical_capacity: "50-300"
+      
+      # Research spaces
+      LABORATORY:
+        description: Scientific or conservation laboratory space
+        annotations:
+          usage_context: research
+          
+      STUDIO:
+        description: Creative or production workspace
+        annotations:
+          usage_context: creative
+      
+      # Library/archive spaces
+      READING_ROOM:
+        description: Research/study area for visitors
+        meaning: hc:ReadingRoom
+        annotations:
+          usage_context: research
+      
+      STUDY_CARREL:
+        description: Individual study booth or station
+        annotations:
+          usage_context: research
+      
+      # Storage spaces
+      STORAGE_ROOM:
+        description: Collection storage space
+        annotations:
+          usage_context: storage
+      
+      VAULT:
+        description: Secure storage for valuable items
+        annotations:
+          usage_context: storage
+          security_level: high
+      
+      # Administrative spaces
+      OFFICE:
+        description: Administrative workspace
+        annotations:
+          usage_context: administrative
+      
+      MEETING_ROOM:
+        description: Conference/meeting space
+        annotations:
+          usage_context: administrative
+      
+      # Public spaces
+      GALLERY:
+        description: Exhibition gallery space
+        meaning: schema:ExhibitionEvent
+        annotations:
+          usage_context: exhibition
+      
+      AUDITORIUM:
+        description: Large performance/presentation venue
+        meaning: schema:EventVenue
+        annotations:
+          usage_context: events
+      
+      # Support spaces
+      RESTROOM:
+        description: Visitor restroom facilities
+        annotations:
+          usage_context: visitor_services
+      
+      CLOAKROOM:
+        description: Coat/bag storage for visitors
+        annotations:
+          usage_context: visitor_services
+      
+      # Unknown
+      UNKNOWN:
+        description: Room type not specified or unknown
+        annotations:
+          usage_context: unspecified

schemas/20251121/linkml/modules/slots/slot_fixes.yaml

@@ -10682,3 +10682,52 @@ fixes:
     type: slot
   - label: TimeSpan
     type: class
+- original_slot_id: https://nde.nl/ontology/hc/slot/date_precision
+  revision:
+  - label: degree_of_certainty
+    type: slot
+  - label: DatePrecision
+    type: class
+- original_slot_id: https://nde.nl/ontology/hc/slot/date_retrieved
+  revision:
+  - label: was_retrieved_at
+    type: slot
+  - label: Timestamp
+    type: class
+- original_slot_id: https://nde.nl/ontology/hc/slot/de
+  revision:
+  - label: has_or_had_language
+    type: slot
+  - label: Language
+    type: class
+    value: de
+- original_slot_id: https://nde.nl/ontology/hc/slot/dealer_name
+  revision:
+  - label: is_or_was_associated_with
+    type: slot
+  - label: ArtDealer
+    type: class
+  - label: has_or_had_name
+    type: slot
+  - label: Name
+    type: class
+- original_slot_id: https://nde.nl/ontology/hc/slot/death_place
+  revision:
+  - label: is_deceased
+    type: slot
+  - label: DeceasedStatus
+    type: class
+  - label: was_or_is_caused_by
+    type: slot
+  - label: CauseOfDeath
+    type: class
+  - label: occurs_or_occurred_at
+    type: slot
+  - label: Place
+    type: class
+- original_slot_id: https://nde.nl/ontology/hc/slot/deceased
+  revision:
+  - label: is_deceased
+    type: slot
+  - label: DeceasedStatus
+    type: class