Initial commit: AirCoding V1.0.0 Alpha architecture baseline

Complete architecture document set with multi-model review remediation:
- Frozen interface contracts, runtime semantics, DB schemas
- Event/tool/error/provider registries
- Scheduler and main agent state machines
- C4 module/code views, solution architecture, baseline V1
- Multi-model review reports and joint assessment
- Phase-gate remediation complete (P0/P1/P2/UX resolved)
- Implementation plan with T-000A through T-045
- Reference folders kept as placeholders only

reference/openai-codex/.codex/skills/babysit-pr/agents/openai.yaml

@@ -0,0 +1,4 @@
+interface:
+  display_name: "PR Babysitter"
+  short_description: "Watch PR review comments, CI, and merge conflicts"
+  default_prompt: "Babysit the current PR: monitor reviewer comments, CI, and merge-conflict status (prefer the watcher’s --watch mode for live monitoring); surface new review feedback before acting on CI or mergeability work, fix valid issues, push updates, and rerun flaky failures up to 3 times. Do not post replies to human-authored review comments unless the user explicitly confirms the exact response. Do not patch unrelated flaky tests, CI infrastructure, dependency outages, runner issues, or other failures that are not caused by the branch. Keep exactly one watcher session active for the PR (do not leave duplicate --watch terminals running). If you pause monitoring to patch review/CI feedback, restart --watch yourself immediately after the push in the same turn. If a watcher is still running and no strict stop condition has been reached, the task is still in progress: keep consuming watcher output and sending progress updates instead of ending the turn. Do not treat a green + mergeable PR as a terminal stop while it is still open; continue polling autonomously after any push/rerun so newly posted review comments are surfaced until a strict terminal stop condition is reached or the user interrupts."