FRE-592: Fix remaining code review blockers and add tests

- Replace in-memory Maps with Drizzle ORM queries for all CRUD operations
- Use integer IDs matching SQLite schema instead of UUIDs
- Fix scriptId to projectId inconsistency in characters and scenes
- Add project ownership verification on all mutation procedures
- Make getCharacter/getScene procedures protected (not public)
- Proper JWT-based userId validation via context
- Add cascade delete for characters/relationships/scenes on project deletion
- Add verifyProjectOwnership helper for authorization checks
- Rewrite tests with createCallerFactory pattern for tRPC v11
- Use better-sqlite3 for in-memory test database
- Split vitest config into separate file from vite config

vite.config.ts

@@ -30,8 +30,4 @@ export default defineConfig({
       },
     },
   },
-  test: {
-    globals: true,
-    environment: 'node',
-  },
 });