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/metadata_service.py

@@ -2,7 +2,6 @@
 
 import logging
 from pathlib import Path
-from typing import Optional
 
 logger = logging.getLogger(__name__)
 
@@ -21,7 +20,6 @@ class MetadataService:
             Dictionary with audio metadata.
         """
         try:
-            import mutagen
             from mutagen import File as MutagenFile
 
             audio = MutagenFile(str(file_path), easy=True)
@@ -68,7 +66,9 @@ class MetadataService:
                         metadata["album"] = tags["album"][0] if isinstance(tags["album"], list) else tags["album"]
 
                     if "albumartist" in tags:
-                        metadata["album_artist"] = tags["albumartist"][0] if isinstance(tags["albumartist"], list) else tags["albumartist"]
+                        metadata["album_artist"] = (
+                            tags["albumartist"][0] if isinstance(tags["albumartist"], list) else tags["albumartist"]
+                        )
 
                     if "date" in tags:
                         metadata["date"] = tags["date"][0] if isinstance(tags["date"], list) else tags["date"]
@@ -77,7 +77,9 @@ class MetadataService:
                         metadata["genre"] = tags["genre"][0] if isinstance(tags["genre"], list) else tags["genre"]
 
                     if "tracknumber" in tags:
-                        metadata["track_number"] = tags["tracknumber"][0] if isinstance(tags["tracknumber"], list) else tags["tracknumber"]
+                        metadata["track_number"] = (
+                            tags["tracknumber"][0] if isinstance(tags["tracknumber"], list) else tags["tracknumber"]
+                        )
 
                 # If no title tag, use filename
                 if "title" not in metadata:
@@ -110,7 +112,6 @@ class MetadataService:
             Dictionary with video metadata.
         """
         try:
-            import mutagen
             from mutagen import File as MutagenFile
 
             video = MutagenFile(str(file_path))