Fix 9 compilation errors across tidal-server and testing/cluster.rs so
that `cargo run -p tidal-server -- standalone` works end-to-end.
Bugs fixed:
- cluster.rs: wrong return types `RetrieveResult`→`Results` and
`SearchResult`→`SearchResults` on retrieve/search helpers
- state.rs: `RegionId` imported from private path; now uses
`tidaldb::replication::RegionId`
- state.rs: missing `Ok()` wrapper on `ServerState::cluster()` return
- state.rs: cluster match arms returned `TidalError` where `ServerError`
required; added `.map_err(ServerError::from)` on write_item,
write_embedding, retrieve, search
- error.rs: `Result<T>` alias lacked default E param; callers in router
used two-arg form `Result<T, AppError>` — changed to
`Result<T, E = ServerError>`
- router.rs: `with_state()` called before cluster routes were added,
making `app` `Router<()>`; restructured to call `with_state` once at end
- router.rs: `TidalErrorWrapper(TidalError)` used to map `QueryError`;
fixed with `|e| TidalErrorWrapper(e.into())`
- router.rs: `Search::limit()` takes `u32` but code cast to `usize`
- router.rs: `bm25_score`/`semantic_score` are `f32` in SearchResultItem
but `f64` in response struct; added `.map(f64::from)` conversion
Also split cluster.rs into cluster.rs + cluster_transport.rs to stay
under the 600-line limit required by CODING_GUIDELINES §9.
Verified all README curl examples work:
POST /items, POST /embeddings, POST /signals, GET /feed, GET /search,
GET /health all return correct HTTP status codes and JSON responses.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
