test(lexicon): clean up obsolete test data files
Remove test data files that are no longer valid after enum → knownValues changes:
**Removed obsolete enum validation tests:**
- post/post-invalid-enum-type.json - knownValues allow unknown types
- community/moderator-invalid-permissions.json - knownValues allow extension
- interaction/share-valid*.json (2 files) - interaction lexicons removed
- interaction/tag-*.json (3 files) - interaction lexicons removed
**Fixed invalid test data:**
- moderation/tribunal-vote-valid.json - corrected invalid AT-URI format
Changed: at://$1/... → at://did:plc:testuser123/...
**Rationale:**
With knownValues (vs strict enums), the lexicon validator accepts unknown
values for extensibility. These test files expected rejection of unknown
enum values, which no longer applies under the knownValues pattern.
**Validation Status:** All 58 lexicons validated successfully
- 15/15 valid test files passing
- 11/11 invalid test files correctly rejected
- 13 record types with test coverage
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude <noreply@anthropic.com>