ryu-tool-registry 0.1.3

Unified tool-catalog primitive for Ryu (#474): the Contract-1 descriptor types (`ToolKind`/`ToolDescriptor`/`DescribedTool`/`DescribedArg`), the swappable `ToolRanker` (BM25 default + an embedder-backed Semantic seam), argument-schema parsing, and the pure search/describe bodies over `ToolDescriptor`. An extracted Core capability crate: in-process by default, consumed as a NON-optional path dependency (the `/api/tools/{search,describe}` endpoints and the mcp_bridge tool-search meta-tool reach it in every build, including lean). The semantic embedder injects via the narrow `ToolEmbedder` trait, so the crate has ZERO dependency on apps/core — the `RegistryTool`→`ToolDescriptor` ingest adapter, the built-in server inventory classification, the Composio live fetch, and the registry-driven embedder choice stay Core-side (`apps/core/src/sidecar/mcp/catalog.rs` + `apps/core/src/tool_registry_host.rs`).