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/teams.py

@@ -1,6 +1,6 @@
 from fastapi import APIRouter, Depends, HTTPException, Query
 from sqlalchemy.ext.asyncio import AsyncSession
-from typing import Annotated, Optional
+from typing import Optional
 from pydantic import BaseModel
 from app.database import get_db
 from app.services.team import TeamService
@@ -26,7 +26,7 @@ class UpdateRoleRequest(BaseModel):
 async def create_team(
     data: CreateTeamRequest,
     user_id: str = Depends(get_current_user_id),
-    db: Annotated[AsyncSession, Depends(get_db)] = None,
+    db: AsyncSession = Depends(get_db),
 ):
     service = TeamService(db)
     try:
@@ -39,7 +39,7 @@ async def create_team(
 @router.get("")
 async def list_teams(
     user_id: str = Depends(get_current_user_id),
-    db: Annotated[AsyncSession, Depends(get_db)] = None,
+    db: AsyncSession = Depends(get_db),
 ):
     service = TeamService(db)
     return {"teams": await service.list_user_teams(user_id)}
@@ -49,7 +49,7 @@ async def list_teams(
 async def get_team(
     team_id: str,
     user_id: str = Depends(get_current_user_id),
-    db: Annotated[AsyncSession, Depends(get_db)] = None,
+    db: AsyncSession = Depends(get_db),
 ):
     service = TeamService(db)
     team = await service.get_team(team_id, user_id)
@@ -63,7 +63,7 @@ async def invite_member(
     team_id: str,
     data: InviteRequest,
     user_id: str = Depends(get_current_user_id),
-    db: Annotated[AsyncSession, Depends(get_db)] = None,
+    db: AsyncSession = Depends(get_db),
 ):
     service = TeamService(db)
     try:
@@ -78,7 +78,7 @@ async def remove_member(
     team_id: str,
     member_id: str,
     user_id: str = Depends(get_current_user_id),
-    db: Annotated[AsyncSession, Depends(get_db)] = None,
+    db: AsyncSession = Depends(get_db),
 ):
     service = TeamService(db)
     success = await service.remove_member(team_id, user_id, member_id)
@@ -91,7 +91,7 @@ async def remove_member(
 async def leave_team(
     team_id: str,
     user_id: str = Depends(get_current_user_id),
-    db: Annotated[AsyncSession, Depends(get_db)] = None,
+    db: AsyncSession = Depends(get_db),
 ):
     service = TeamService(db)
     success = await service.leave_team(team_id, user_id)
@@ -106,7 +106,7 @@ async def update_member_role(
     member_id: str,
     data: UpdateRoleRequest,
     user_id: str = Depends(get_current_user_id),
-    db: Annotated[AsyncSession, Depends(get_db)] = None,
+    db: AsyncSession = Depends(get_db),
 ):
     service = TeamService(db)
     if data.role not in ("admin", "member", "viewer"):