v2.0.144

v2.0.144 - WebFetch completed document handling

This release fixes the lab-gated native WebFetch path when the language server
has already executed read_url_content and returned a real web_document.

• Completed read_url_content.web_document steps are no longer surfaced to
  OpenAI clients as dead tool-call proposals. The proxy now preserves Cascade's
  final assistant text with finish_reason="stop".
• If Cascade returns a completed WebFetch document but no final text, the proxy
  falls back to the fetched document body as assistant content.
• Pending WebFetch permission steps without a document keep the existing
  proposal/wait behavior, and Bash/Read/Grep native proposal semantics are
  unchanged.
• Proto trace classification now checks completed_web_document before
  pending_permission, so steps that contain both web_document and a
  requested-interaction echo are classified as completed.