Add docker-compose, RUNBOOK.md, and docker Makefile target

- docker-compose.yml: single service with data volume, ports 8443/9443/8080
- RUNBOOK.md: health checks, common operations (start/stop/backup/init),
  FIDO2 key registration, incident procedures (won't start, DB corruption,
  cert expiry, disk full, sync failures), escalation path
- Makefile: added docker target

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

deploy/docker/docker-compose.yml

@@ -0,0 +1,18 @@
+version: "3.8"
+
+services:
+  eng-pad-server:
+    build:
+      context: ../..
+      dockerfile: Dockerfile
+    ports:
+      - "8443:8443"   # REST API (HTTPS)
+      - "9443:9443"   # gRPC (TLS)
+      - "8080:8080"   # Web UI
+    volumes:
+      - data:/srv/eng-pad-server
+    restart: unless-stopped
+
+volumes:
+  data:
+    driver: local