23 tests covering the full JSON-RPC 2.0 protocol surface:
initialize handshake, silent notifications/initialized, tools/list
schema, tools/call with and without args, unknown tool error,
unknown method error, and invalid JSON resilience.
Fixed assert helpers to use grep -qF -- to prevent leading-dash
patterns (like -32601) from being parsed as grep flags.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
