Remove 229 custodian YAML files containing invalid characters in GHCIDs:
- Ampersand (&) in abbreviations (e.g., BM&HS, UNL&AG, DR&IMSM)
- Parentheses in abbreviations (e.g., WHO(RA, VK(, SL()
- Unicode characters in filenames (Ö, Ä, Å, É, İ, Ż, etc.)
These files are replaced with corrected versions using alphabetic-only
abbreviations per AGENTS.md Rule 8 (Special Characters MUST Be Excluded).
Related scripts updated for location resolution.
