fix: CORS/API 500 issues, switch to native tabbar, restore quick-actions

- Backend: guest UUID format fix, /auth/me guest branch, UUID validation in deps.py, CORS config fix
- Frontend: switch to native tabbar (custom: false), cleanup App.vue, redesign quick-actions with colored icons, conditional wechat login, proxy API requests via Vite

backend/app/api/v1/auth.py

@@ -82,7 +82,7 @@ async def login(
 
 @router.post("/login/guest")
 async def guest_login():
-    guest_id = f"guest_{uuid.uuid4().hex[:12]}"
+    guest_id = str(uuid.uuid4())
     access_token = create_access_token(
         {"sub": guest_id, "tier": "guest", "role": "guest", "is_guest": True},
         expires_delta=timedelta(hours=24)
@@ -109,8 +109,18 @@ async def refresh(data: RefreshRequest):
     if not payload or payload.get("type") != "refresh":
         raise HTTPException(status_code=401, detail="Invalid refresh token")
 
+    # 保留游客/角色等信息
+    extra = {}
+    if payload.get("is_guest"):
+        extra = {"is_guest": True, "tier": "guest", "role": "guest"}
+    else:
+        extra = {
+            "tier": payload.get("tier", "free"),
+            "role": payload.get("role", "user"),
+        }
+
     return {
-        "access_token": create_access_token({"sub": payload["sub"]}),
+        "access_token": create_access_token({"sub": payload["sub"], **extra}),
         "token_type": "bearer",
     }
 
@@ -127,6 +137,18 @@ async def get_me(
     if not payload:
         raise HTTPException(status_code=401, detail="Invalid token")
 
+    if payload.get("is_guest"):
+        return {
+            "id": payload["sub"],
+            "phone": None,
+            "username": "游客用户",
+            "tier": "guest",
+            "role": "guest",
+            "is_guest": True,
+            "settings": {},
+            "created_at": None,
+        }
+
     result = await db.execute(select(User).where(User.id == payload["sub"]))
     user = result.scalar_one_or_none()
     if not user: