feat: silent wechat login, marketing tab optimization, admin page foundation

- Add silent WeChat login for MP/browser environments
- Fix Python 3.6 compatibility (remove typing.Annotated usage)
- Marketing page: tab-based content generation with category support
- Translate page: add auto-detect language default
- Homepage: add TTS playback, announcement ticker, remove redundant quick-actions
- Fix FAB button overlap with custom tabbar on customers/quotation pages
- Make openai/anthropic imports lazy for Python 3.6 compat

backend/app/api/v1/auth.py

@@ -2,7 +2,7 @@ from fastapi import APIRouter, Depends, HTTPException, status, Header
 from fastapi.security import OAuth2PasswordRequestForm
 from sqlalchemy.ext.asyncio import AsyncSession
 from sqlalchemy import select
-from typing import Annotated, Optional
+from typing import Optional
 import uuid
 from app.database import get_db
 from app.models.user import User
@@ -31,7 +31,7 @@ class RefreshRequest(BaseModel):
 
 
 @router.post("/register")
-async def register(data: RegisterRequest, db: Annotated[AsyncSession, Depends(get_db)] = None):
+async def register(data: RegisterRequest, db: AsyncSession = Depends(get_db)):
     existing = await db.execute(select(User).where(User.phone == data.phone))
     if existing.scalar_one_or_none():
         raise HTTPException(status_code=400, detail="Phone already registered")
@@ -56,8 +56,8 @@ async def register(data: RegisterRequest, db: Annotated[AsyncSession, Depends(ge
 
 @router.post("/login", response_model=LoginResponse)
 async def login(
-    form: Annotated[OAuth2PasswordRequestForm, Depends()],
-    db: Annotated[AsyncSession, Depends(get_db)] = None,
+    form: OAuth2PasswordRequestForm = Depends(),
+    db: AsyncSession = Depends(get_db),
 ):
     result = await db.execute(select(User).where(User.phone == form.username))
     user = result.scalar_one_or_none()
@@ -128,7 +128,7 @@ async def refresh(data: RefreshRequest):
 @router.get("/me")
 async def get_me(
     authorization: Optional[str] = Header(None, alias="Authorization"),
-    db: Annotated[AsyncSession, Depends(get_db)] = None,
+    db: AsyncSession = Depends(get_db),
 ):
     if not authorization or not authorization.startswith("Bearer "):
         raise HTTPException(status_code=401, detail="Missing token")
@@ -178,8 +178,17 @@ class WeChatLoginRequest(BaseModel):
     iv: str = ""
 
 
+@router.get("/wechat/config")
+async def wechat_config():
+    from app.config import settings
+    return {
+        "available": bool(settings.WECHAT_APP_ID and settings.WECHAT_APP_SECRET),
+        "app_id": settings.WECHAT_APP_ID or "",
+    }
+
+
 @router.post("/wechat-login")
-async def wechat_login(data: WeChatLoginRequest, db: Annotated[AsyncSession, Depends(get_db)] = None):
+async def wechat_login(data: WeChatLoginRequest, db: AsyncSession = Depends(get_db)):
     from app.services.wechat import wechat_service
 
     session = await wechat_service.code2session(data.code)
@@ -216,7 +225,7 @@ async def wechat_login(data: WeChatLoginRequest, db: Annotated[AsyncSession, Dep
 async def update_settings(
     data: SettingsUpdate,
     authorization: Optional[str] = Header(None, alias="Authorization"),
-    db: Annotated[AsyncSession, Depends(get_db)] = None,
+    db: AsyncSession = Depends(get_db),
 ):
     if not authorization or not authorization.startswith("Bearer "):
         raise HTTPException(status_code=401, detail="Missing token")