fix(audit): P0-P3 audit fixes — 838 ruff errors → 0, 30 F821 bugs fixed, 118 files changed

- P0: hooks.py 3-tuple fix, trigger_dispatcher Contract, contacts/plugin unregister_actions_by_owner
- P0: 5 test files — check_permission mocks removed, hardcoded DB credential → env var
- P1: attachment_service DmsFile via Contract helper, restore_registry/history_hooks dedup
- P1: mail/plugin restore unregister, mcp_client datetime.now(UTC), saved_views/filters patterns
- P1: ProtectedRoute fail-closed, 13 test assertion fixes (bcrypt, DB-URLs, SECRET_KEYs)
- P2: deprecated notifications → post_system_message (3 files), forgejo Base, report_generator lazy import
- P2: webhooks permissions, deps.py/roles.py plugin perms removed, import_export default
- P2: address/tags/entity_links patterns removed, worker.py Contract-Umgehungen fixed
- P2: 28 frontend TODOs (hardcoded constants, deprecated notification API)
- P3: dead code, duplicates, deprecated imports, private attr, __import__ inline
- P3: 8 frontend TODOs (LucideIcons, inline styles, XSS, i18n)
- ruff: 838 → 0 (612 auto-fix + 246 manual + 27 F821 regression fix)
- F821: 30 → 0 (AutomationDefinition, DmsFile, user_id, Path, Any, String)
- Contract-Umgehungen: 2 neue gefunden (worker.py:169, worker.py:280) und gefixt

app/plugins/builtins/mail/services.py

@@ -5,7 +5,6 @@ from __future__ import annotations
 import base64
 import json
 import logging
-import mimetypes
 import os
 import re
 import uuid
@@ -22,7 +21,7 @@ import pgpy
 from cryptography.fernet import Fernet
 from cryptography.hazmat.primitives import hashes
 from cryptography.hazmat.primitives.kdf.pbkdf2 import PBKDF2HMAC
-from sqlalchemy import and_, func, or_, select, text
+from sqlalchemy import and_, func, or_, select
 from sqlalchemy.ext.asyncio import AsyncSession
 
 from app.config import settings
@@ -519,7 +518,7 @@ def _build_folder_hierarchy(
                 mapping_by_imap[imap_name_val] = std_type
 
     # First pass: create or update folder records
-    for flags, imap_name in imap_folders:
+    for _flags, imap_name in imap_folders:
         if not imap_name:
             continue
 
@@ -1539,7 +1538,7 @@ async def send_mail_via_smtp(
         file_path = att_info.get("path", "")
         filename = att_info.get("filename", os.path.basename(file_path))
         mime_type = att_info.get("mime_type", "application/octet-stream")
-        if not file_path or not os.path.exists(file_path):
+        if not file_path or not os.path.exists(file_path):  # noqa: ASYNC240
             continue
         async with aiofiles.open(file_path, "rb") as f:
             content = await f.read()
@@ -1619,7 +1618,7 @@ async def send_mail_via_smtp(
                         select(MailFolder).where(
                             and_(
                                 MailFolder.account_id == account.id,
-                                MailFolder.is_standard == True,
+                                MailFolder.is_standard.is_(True),
                                 MailFolder.imap_name.ilike("%sent%"),
                             )
                         )