fix(mcp): rewrite hallucinated `tools/call` argument names (#2598)

Some LLM clients send `context7CompatibleLibraryID`/`userQuery` instead of
the canonical `libraryId`/`query` — likely echoing phrasing from the tool
descriptions — and trip Zod validation before the tool ever runs.

Hook `Transport.onmessage` (set before `server.connect()` so the SDK chains
its dispatch over it) and rewrite those two keys in place on `tools/call`
requests where the canonical key is absent. Published `tools/list` schemas
are unchanged; the rewrite is a server-side compatibility shim.