feat: Token Broker infrastructure (HRT-205)

- PostgreSQL dedie Docker (postgres:16-alpine, port 5434)
- 6 tables: api_tokens, refresh_tokens, token_audit_log, clients, providers, token_usage
- Init SQL + Flask init_db() mis a jour
- Systemd service token-broker (port 8783)
- Deploy script infra/scripts/deploy_token_broker.sh
- Docker compose broker (docker-compose.broker.yml)
- Health check OK: status=ok, database=connected

Co-Authored-By: Paperclip <noreply@paperclip.ing>

docker-compose.broker.yml

@@ -0,0 +1,32 @@
+# Token Broker Infrastructure
+# PostgreSQL dedicated instance on port 5434
+networks:
+  turf-net:
+    driver: bridge
+
+services:
+  token-broker-db:
+    image: postgres:16-alpine
+    container_name: token-broker-db
+    restart: unless-stopped
+    environment:
+      POSTGRES_DB: token_broker
+      POSTGRES_USER: token_broker
+      POSTGRES_PASSWORD: ${TOKEN_BROKER_DB_PASSWORD:-CHANGE_ME_PASSWORD}
+    volumes:
+      - token-broker-pgdata:/var/lib/postgresql/data
+      - ./infra/postgres/token_broker_init.sql:/docker-entrypoint-initdb.d/init.sql:ro
+    healthcheck:
+      test: ["CMD-SHELL", "pg_isready -U token_broker -d token_broker"]
+      interval: 10s
+      timeout: 5s
+      retries: 5
+      start_period: 30s
+    networks:
+      - turf-net
+    ports:
+      - "127.0.0.1:5434:5432"
+
+volumes:
+  token-broker-pgdata:
+    driver: local