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/.github/workflows/cargo-deny.yml

@@ -0,0 +1,29 @@
+name: cargo-deny
+
+on:
+  pull_request:
+  push:
+    branches:
+      - main
+
+jobs:
+  cargo-deny:
+    runs-on: ubuntu-latest
+    defaults:
+      run:
+        working-directory: ./codex-rs
+    steps:
+      - name: Checkout
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          ref: ${{ github.event_name == 'pull_request' && github.event.pull_request.head.sha || github.sha }}
+          persist-credentials: false
+
+      - name: Install Rust toolchain
+        uses: dtolnay/rust-toolchain@a0b273b48ed29de4470960879e8381ff45632f26 # 1.93.0
+
+      - name: Run cargo-deny
+        uses: EmbarkStudios/cargo-deny-action@82eb9f621fbc699dd0918f3ea06864c14cc84246 # v2
+        with:
+          rust-version: 1.93.0
+          manifest-path: ./codex-rs/Cargo.toml