Addresses a review finding: cargo fmt --check was failing on the V0/L1/L2 crates (and some pre-existing engine drift). cargo fmt --all --check is now clean. No behavior change.
Move api.rs (HTTP request/response DTOs + OpenAPI schemas) into omnigraph-api-types (deps: engine, compiler, queries, serde, serde_json, utoipa). Repoint crate::queries::StoredQuery -> omnigraph_queries. Relocate the two catalog-projection tests here, where query_catalog_entry lives, eliminating the queries<->api dev-dep cycle (no cycle, tests at their boundary). Server aliases via 'pub use omnigraph_api_types as api;'. openapi.json byte-identical (drift test passes; no regen). 2 api-types tests pass; server+cli compile. No behavior change.
