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/

packages/opencode/test/fixture/plugin-meta-worker.ts

@@ -0,0 +1,19 @@
+const raw = process.argv[2]
+if (!raw) throw new Error("Missing worker payload")
+
+const value = JSON.parse(raw)
+if (!value || typeof value !== "object") {
+  throw new Error("Invalid worker payload")
+}
+
+const msg = Object.fromEntries(Object.entries(value))
+if (typeof msg.file !== "string" || typeof msg.spec !== "string" || typeof msg.target !== "string") {
+  throw new Error("Invalid worker payload")
+}
+if (typeof msg.id !== "string") throw new Error("Invalid worker payload")
+
+process.env.OPENCODE_PLUGIN_META_FILE = msg.file
+
+const { PluginMeta } = await import("../../src/plugin/meta")
+
+await PluginMeta.touch(msg.spec, msg.target, msg.id)