feat: Character Sheet Setup — players create and manage their character sheets

[Fortinbra]

Players set up their character sheets (race, class, level, ability scores, HP, AC, backstory, etc.). Sheets are associated with a player in a campaign. Used by the AI DM (Ollama) during sessions.

[Fortinbra]

Spec revised: character options (class, race, spells) are now constrained FK selections from DM-managed reference tables. CharacterClass and CharacterRace entities added. Discord flow updated to use SelectMenuComponent after modal. Placeholder seed data defined.

[Fortinbra]

✅ Spec approved by The Doctor. Ready for Danny's TDD kickoff ceremony.

Review findings:

• ✓ Spec correctly revised to use constrained character options (commit 5ec044b)
• ✓ CharacterClassId and CharacterRaceId are uuid FKs (not free-text varchar)
• ✓ CharacterClasses and CharacterRaces reference tables defined with IsAvailable flag
• ✓ Discord SelectMenuComponent flow documented (3-step due to Discord platform limitation)
• ✓ Seed data migration specified (D&D 5e basic classes and races)
• ✓ API endpoints for GET /api/character-options/classes and /api/character-options/races
• ✓ AbilityScores as EF Core owned entity is sound

Watch points:

• Danny must test Discord SelectMenu population from reference tables
• Danny must test IsAvailable gating (character sheet creation rejected if class/race has IsAvailable=false)

Dependencies: Spec #4 (PlayerCharacter), Spec #8 (CampaignPlayer)

Agent assignment: Rory (CharacterClass/Race entities, CharacterSheet with FKs, API endpoints, Discord SelectMenu interactions), Clara (UI for character options management)

[Fortinbra]

✅ Spec #9 (Character Sheet Setup) fully implemented and verified. All CharacterSheet tests passing (10 Core + 6 API). Full test suite: 280/285 tests passing (5 expected JWT failures excluded).