cad83ab53e
Shrink the execute tool description to namespaces only (server name, tool
count, and a brief note reused from the server's MCP instructions) instead of
inlining every tool signature, so the prompt stays small for large catalogs.
Add in-sandbox discovery: `tools.search(query, { namespace?, limit? })` returns
ranked tool paths + descriptions, and `tools.describe(path)` returns the full
signature and input schema on demand (with tool_not_found suggestions). The
proxy is now recursive so both `tools.<server>.<tool>(args)` and the dotted
`tools[path](args)` returned by search resolve to the catalog key.