fix(jsonrpc): report malformed input

[benbrandt]

Summary

• return JSON-RPC parse errors for malformed NDJSON and WebSocket frames
• return invalid-request errors for parsed primitives and malformed calls
• never reply to malformed response-shaped messages
• reject a matching pending request when its response envelope is malformed
• keep transports usable for subsequent valid messages

Testing

• npm run build
• npm run lint
• npm run format:check
• npm test (836 tests)