feat(aircoding): AirCoding V2 baseline — deterministic multi-agent architecture

Forked from OpenCode v1.17.4 with multi-agent system:
- 5 agents: aircoding, scheduler, worker, architect, reviewer
- Deterministic DAG scheduling engine (coordinator_tick)
- Tool whitelists as hard enforcement
- AirCoding validation plugin
- V1 requirements: C4 docs, ADR, AGENTS.md, debug-log.md
- Design documents in docs/

.github/workflows/opencode.yml

@@ -0,0 +1,34 @@
+name: opencode
+
+on:
+  issue_comment:
+    types: [created]
+  pull_request_review_comment:
+    types: [created]
+
+jobs:
+  opencode:
+    if: |
+      contains(github.event.comment.body, ' /oc') ||
+      startsWith(github.event.comment.body, '/oc') ||
+      contains(github.event.comment.body, ' /opencode') ||
+      startsWith(github.event.comment.body, '/opencode')
+    runs-on: blacksmith-4vcpu-ubuntu-2404
+    permissions:
+      id-token: write
+      contents: read
+      pull-requests: read
+      issues: read
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4.3.1
+
+      - uses: ./.github/actions/setup-bun
+
+      - name: Run opencode
+        uses: anomalyco/opencode/github@2c14fc5586fe0b88e5c04732d2e846769cc35671 # latest
+        env:
+          OPENCODE_API_KEY: ${{ secrets.OPENCODE_API_KEY }}
+          OPENCODE_PERMISSION: '{"bash": "deny"}'
+        with:
+          model: opencode/claude-opus-4-5