feat(feedback): implement user feedback collection system with email reporting

Backend:
- Add user_feedback table with RLS policy
- Create feedback submission API (multipart/form-data)
- Implement xlsx report generation with embedded images
- Add scheduled email delivery via Feishu SMTP
- Create HTML email templates (daily_report, no_feedback)

Frontend:
- Add feedback screen with type selection and image picker
- Support anonymous submission via skipAuth flag
- Collect device info and app version

Protocol:
- Document feedback API contract and error codes
- Update http-error-codes.md with FEEDBACK_* codes

backend/src/v1/feedback/dependencies.py

@@ -0,0 +1,49 @@
+from __future__ import annotations
+
+import asyncio
+from typing import Annotated
+from uuid import UUID
+
+from fastapi import Depends, Header
+from sqlalchemy.ext.asyncio import AsyncSession
+
+from core.auth.models import CurrentUser
+from core.db import get_db
+from services.base.supabase import supabase_service
+from v1.feedback.repository import FeedbackRepository
+from v1.feedback.service import FeedbackService
+
+
+async def get_optional_user(
+    authorization: str | None = Header(default=None),
+) -> CurrentUser | None:
+    if not authorization:
+        return None
+
+    scheme, _, token = authorization.partition(" ")
+    if scheme.lower() != "bearer" or not token:
+        return None
+
+    try:
+        client = supabase_service.get_client()
+        response = await asyncio.to_thread(client.auth.get_user, token)
+        user = getattr(response, "user", None)
+        user_id = getattr(user, "id", None)
+        if not isinstance(user_id, str) or not user_id:
+            return None
+        return CurrentUser(
+            id=UUID(user_id),
+            email=getattr(user, "email", None),
+            role=getattr(user, "role", None),
+        )
+    except Exception:
+        return None
+
+
+def get_feedback_service(
+    session: Annotated[AsyncSession, Depends(get_db)],
+) -> FeedbackService:
+    return FeedbackService(
+        repository=FeedbackRepository(session=session),
+        storage=supabase_service,
+    )