refactor: 移除 LiteLLM proxy 架构，后端直连 Provider API

- 移除 backend/scripts/build_litellm_proxy_config.py
- 简化 LiteLLMService，移除 run_completion_with_cost 方法
- AgentScopeRunner 改为从 LlmFactory 获取 api_base 和 api_key
- 部署配置移除 litellm/litellm-config-job 服务
- Flutter 新增 AuthBootScreen 引导页
- Android 添加通知权限 (POST_NOTIFICATIONS, RECEIVE_BOOT_COMPLETED, SCHEDULE_EXACT_ALARM)
- 优化 LocalNotificationService 调度失败 fallback
- 更新 manifest.json (version 3)

infra/docker/docker-compose.yml

@@ -19,50 +19,6 @@ services:
             timeout: 3s
             retries: 5
 
-    litellm-config-job:
-        build:
-            context: ../..
-            dockerfile: backend/Dockerfile
-        image: social-local-backend
-        container_name: social-local-litellm-config-job
-        restart: "no"
-        env_file:
-            - ../../.env
-        environment:
-            - PYTHONPATH=/app/backend/src
-        command: >
-            uv run python backend/scripts/build_litellm_proxy_config.py --output /config/litellm-proxy-config.yaml
-        volumes:
-            - litellm_config:/config
-        depends_on:
-            redis:
-                condition: service_healthy
-
-    litellm:
-        image: ghcr.io/berriai/litellm@sha256:b959a1816fa454a14d2842242d0fa1cd0d39f96fc94d3a1f4e1de4e48e2398c6
-        container_name: social-local-litellm
-        restart: unless-stopped
-        env_file:
-            - ../../.env
-        ports:
-            - "${SOCIAL_LITELLM__PORT:-3875}:${SOCIAL_LITELLM__PORT:-3875}"
-        volumes:
-            - litellm_config:/config:ro
-        command:
-            [
-                "--config",
-                "/config/litellm-proxy-config.yaml",
-                "--host",
-                "0.0.0.0",
-                "--port",
-                "${SOCIAL_LITELLM__PORT:-3875}",
-            ]
-        depends_on:
-            redis:
-                condition: service_healthy
-            litellm-config-job:
-                condition: service_completed_successfully
-
     init-job:
         build:
             context: ../..
@@ -91,4 +47,3 @@ services:
 
 volumes:
     redis_data:
-    litellm_config: