Add CI/CD pipelines, NSIS installer, ES module bundling, and ruff linting

- Add Gitea Actions workflows: test.yml (lint + test on push/PR) and
  release.yml (build + NSIS installer + upload on v* tags)
- Add NSIS installer with optional desktop shortcut and auto-start
- Add esbuild bundler: ES module migration with IIFE bundle output
- Add build-dist-windows.sh for cross-building Windows distribution
- Fix all ruff lint errors (import sorting, unused imports, line length)
- Remove redundant scripts (start-server.bat, stop-server.bat,
  start-server-background.vbs)
- Update CLAUDE.md with CI/CD and release documentation

media_server/services/browser_service.py

@@ -1,12 +1,10 @@
 """Browser service for media file browsing and path validation."""
 
 import logging
-import os
 import stat as stat_module
 import time
 from datetime import datetime
 from pathlib import Path
-from typing import Optional
 
 from ..config import settings