v0.11.0

Security

• Added an authenticated, bounded push callback receiver with a unique route and high-entropy token
  for every trial. It accepts standard Bearer authentication plus the legacy token header emitted
  by A2A Python SDK 1.1.1. Accepted events are bound to the task and context returned by the initial
  A2A request, exact retries are deduplicated, and public callback URLs require HTTPS. Plain HTTP is
  limited to loopback and private-network hosts.
• Limited callback concurrency, active subscriptions, request and aggregate body sizes, event
  counts, path length, and connection lifetime. Malformed requests, ambiguous headers, unsupported
  media types, and unknown protobuf fields are rejected before evaluation.

Bug fixes

• Rejected callbacks that omit the expected context ID, and canceled active connection handlers
  when the receiver closes so no accepted request outlives the run.
• Closed a newly registered callback subscription when message sending, file preparation, task-ID
  validation, or binding fails, preventing failed trials from consuming the run-wide subscription
  limit.
• Started the await_push timeout when the wait action begins instead of when the callback was
  registered, and surfaced authenticated invalid deliveries immediately instead of waiting for a
  timeout.

Features

• Added black-box push delivery contracts. A turn can register an inline A2A push configuration,
  return its task immediately, and use action: await_push to assert the state trajectory, text,
  structured data, files, timing, AP2 proofs, and global invariants of the delivered events.
• Added a loopback callback listener for local agents and explicit listen_host, listen_port, and
  public_url settings for remote agents behind an HTTPS reverse proxy or tunnel.

Documentation

• Replaced the README's toy capital-city example with a realistic structured routing contract and
  a compact risk-to-capability map covering behavioral drift, nondeterminism, lifecycle, deployment
  comparison, leak detection, and AP2 verification.
• Added a focused push notification guide covering local and remote setup, callback routing,
  authentication, lifecycle rules, bounds, and failure behavior without expanding the README into
  a reference manual.

Maintenance

• Added real JSON-RPC and HTTP+JSON push exchanges plus an interoperability test that delivers an
  event through the official A2A Python SDK sender. Extended configuration, protocol rejection,
  cleanup, schema, and runner coverage while retaining the 99% coverage gate.
• Added the lightweight HTTP/1.1 parser as a direct dependency and included the callback receiver
  in deterministic mutation testing.