fix: implement P1-P4 code review recommendations

Priority 1 (Critical):
- Enable TypeScript strict mode in tsconfig.json
- Replace gray-matter with effect-mdx in validator.ts
- Remove unused gray-matter dependency from ep-cli

Priority 2 (Architectural):
- Refactor StateStore to use @effect/platform FileSystem
- Fix Effect.runSync in Logger services (shouldLog returns Effect)
- Add schema.ts files for db, qa, display, execution services
- Logger consolidation already in place via re-exports

Priority 3 (Code Quality):
- Align dependency versions across packages
- Add schema.ts files for git, ingest, tui services
- Add @deprecated tags to legacy validation functions

Priority 4 (Testing & Documentation):
- Add ep-admin to vitest workspace
- Add README.md files for qa, ingest, tui, publish services
- Fix vitest.workspace.ts to use array export format