ci/docs: enforce protocol check and deprecate control api

.github/workflows/ci.yml

@@ -72,6 +72,10 @@ jobs:
         if: matrix.runtime == 'node'
         run: pnpm build
 
+      - name: Protocol check (node)
+        if: matrix.runtime == 'node'
+        run: pnpm protocol:check
+
       - name: Lint (bun)
         if: matrix.runtime == 'bun'
         run: bunx biome check src

docs/control-api.md

@@ -1,5 +1,7 @@
 # Control channel API (newline-delimited JSON)
 
+**Deprecated:** superseded by the WebSocket Gateway protocol (`clawdis gateway`, see `docs/architecture.md` and `docs/gateway.md`). Use only for legacy builds predating the Gateway rollout.
+
 Endpoint: `127.0.0.1:18789` (TCP, localhost only). Clients reach it via SSH port forward in remote mode.
 
 ## Frame format