feat(routes): 迁移首页/静态资源 + /auth/me 认证状态

- web/routers/index.py：GET / 首页，用 Jinja2 以 Flask 同口径渲染
  （keep_trailing_newline=False）——输出与 Flask render_template 逐字节一致
- web/app.py：挂载 /static 静态资源（site_auth.js 等，与 Flask 同目录）
- web/routers/auth_status.py：/api/v1/auth/me 认证状态
  · user/duration_text/announcement/smtp_configured/register_credits 逐字段对齐
- core/repo.py：补 get_announcement / get_smtp_config / smtp_configured 异步读

契约奇偶校验：28 项全 OK（新增 index 逐字节、auth:me）；
验证：pytest 51/51；ruff All checks passed；pyright 0 errors；
uvicorn 实跑 / 与 /static 与 /api/v1/* 均 200。

web/app.py

@@ -14,15 +14,19 @@
 """
 
 from contextlib import asynccontextmanager
+from pathlib import Path
 
 from fastapi import FastAPI
+from fastapi.staticfiles import StaticFiles
 
 from core.config import APP_VERSION
 from core.security import init_secret_key
 from web.errors import install_error_handlers
 from web.middleware import ResponseHygieneMiddleware
 from web.routers import account as account_router
+from web.routers import auth_status as auth_status_router
 from web.routers import delivery as delivery_router
+from web.routers import index as index_router
 from web.routers import music as music_router
 from web.routers import podcast as podcast_router
 from web.routers import site as site_router
@@ -70,6 +74,11 @@ def create_app(serve_flask_fallback: bool = False) -> FastAPI:
     # 响应侧统一处理：安全头 + 音频直链签名保护 + 版本指纹抹除
     app.add_middleware(ResponseHygieneMiddleware)
 
+    # 静态资源（/static/site_auth.js 等）——与 Flask static_folder 同目录
+    _static_dir = Path(__file__).resolve().parent.parent / 'static'
+    if _static_dir.is_dir():
+        app.mount('/static', StaticFiles(directory=str(_static_dir)), name='static')
+
     # 已迁移路由：统一挂 /api/v1（迁移期与 Flask 根路径并存，便于对比）
     app.include_router(system_router.router, prefix='/api/v1', tags=['system'])
     app.include_router(site_router.router, prefix='/api/v1', tags=['site'])
@@ -79,6 +88,9 @@ def create_app(serve_flask_fallback: bool = False) -> FastAPI:
     app.include_router(tasks_router.router, prefix='/api/v1', tags=['tasks'])
     app.include_router(delivery_router.router, prefix='/api/v1', tags=['delivery'])
     app.include_router(stream_router.router, prefix='/api/v1', tags=['stream'])
+    app.include_router(auth_status_router.router, prefix='/api/v1', tags=['auth'])
+    # 首页与静态资源（迁移完成形态；fallback 模式下同路径也能由 Flask 提供）
+    app.include_router(index_router.router, tags=['index'])
 
     install_error_handlers(app)