Apply comprehensive atProto Lexinomicon best practices to all lexicon schemas: **Extensibility (16 enum → knownValues changes):** - Convert all closed enums to knownValues for federation compatibility - Affected fields: sort, timeframe, postType, vote, blockedBy, embedType - Allows unknown values from other implementations gracefully - Enables future additions without breaking existing clients **Internationalization (11+ maxGraphemes additions):** - Add maxGraphemes constraints to all string fields with maxLength - Ensures proper UTF-8 multi-byte character handling - Affected: community names, descriptions, alt text, edit notes, titles, content - Follows 10-20 byte-to-grapheme ratio for international text **Schema Organization (3 reference fixes):** - Fix feed references: getTimeline#feedViewPost → defs#feedViewPost - Fix community references: list#communityView → defs#communityView - Remove unimplemented aspectRatio reference from video.json - Centralizes definitions in defs.json files per best practices **Files Modified:** - embed: external.json, images.json, video.json - feed: getAll.json, getCommunity.json, getDiscover.json, getTimeline.json - community: defs.json, profile.json, search.json - community/post: get.json, search.json, update.json **Impact:** No breaking changes - existing code uses defensive validation patterns that work seamlessly with knownValues. All validation tests passing. References: https://github.com/bluesky-social/atproto/discussions/4245 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>