fix: cargo fmt on FTS5 migration code

## Summary
PR #664 fails CI Format check. Schema migration code in `schema.rs:972` needs `cargo fmt`.

## Fix
Run `cargo fmt --all` and push to `feat/fts5-memory-type`.

## Verification
```bash
cargo fmt --all -- --check
```

## Workflow
- Push fix to `feat/fts5-memory-type`
- Assignee: CTO
- Relates: PR #664