feat(docker): core compose + OpenClaw entrypoint (MS22-P1j)

docker/README.md

@@ -0,0 +1,40 @@
+# Mosaic Docker (Core Services)
+
+This folder includes the Compose stack for **core Mosaic services only**:
+
+- `mosaic-api`
+- `mosaic-web`
+- `postgres`
+
+User OpenClaw containers are **not** defined in Compose. They are created and managed dynamically by the API's `ContainerLifecycleService` through Docker socket access.
+
+## Start the stack
+
+```bash
+docker compose -f docker/mosaic-compose.yml up -d
+```
+
+## Required environment variables
+
+- `DATABASE_URL`
+- `MOSAIC_SECRET_KEY`
+- `DATABASE_PASSWORD`
+
+Use [`docker/.env.example`](./.env.example) as a starting point.
+
+## Architecture overview
+
+See the design doc: [`docs/design/MS22-DB-CENTRIC-ARCHITECTURE.md`](../docs/design/MS22-DB-CENTRIC-ARCHITECTURE.md)
+
+`mosaic-agents` is an internal-only bridge network reserved for dynamically created user containers.
+
+## OpenClaw entrypoint behavior
+
+`docker/openclaw-entrypoint.sh` is intended for dynamically created user OpenClaw containers:
+
+1. Validates required env vars (`MOSAIC_API_URL`, `AGENT_TOKEN`, `AGENT_ID`).
+2. Fetches agent-specific OpenClaw config from Mosaic API internal endpoint.
+3. Writes the config to `/tmp/openclaw.json`.
+4. Starts OpenClaw gateway with `OPENCLAW_CONFIG_PATH=/tmp/openclaw.json`.
+
+`docker/openclaw-healthcheck.sh` probes `http://localhost:18789/health` for container health.