v0.4.0

Added

• Expose qe_run_openai_compat_agent as an experiment-only, env-gated standalone MCP runner for OpenAI-compatible endpoints.
• Add server wiring, schema/help/list dispatch, smoke coverage, and MCP stdio wiring tests.

Changed

• Keep qe_delegate_agent target engines limited to claude/codex while documenting openai-compat as standalone.
• Update README migration notes and tool surface documentation for 0.4.0.