fix: replace emoji characters with ASCII-safe markers for Windows compatibility

- Replace Unicode emoji (✓, ⚠️) with [OK] and [WARN] in audio_preprocessor.py
  to prevent UnicodeEncodeError on Windows console (cp1252 codec)
- Add auto-update dependencies function to bot.py for easier maintenance
- Remove setup_linux.sh (no longer needed)
- Update .gitignore to exclude VS Code launch.json

audio_preprocessor.py

@@ -190,16 +190,16 @@ def print_audio_analysis(file_path: str) -> None:
     print(f"\n{'=' * 50}")
     print(f"Audio Analysis: {info['path']}")
     print(f"{'=' * 50}")
-    print(f"  Sample Rate:    {info['sample_rate']} Hz {'⚠️  (should be 22050)' if info['needs_resampling'] else '✓'}")
+    print(f"  Sample Rate:    {info['sample_rate']} Hz {'[WARN] (should be 22050)' if info['needs_resampling'] else '[OK]'}")
     print(f"  Duration:       {info['duration_seconds']:.2f}s", end="")
     if info['is_too_short']:
-        print(" ⚠️  (too short, aim for 5-15s)")
+        print(" [WARN] (too short, aim for 5-15s)")
     elif info['is_too_long']:
-        print(" ⚠️  (quite long, 5-15s is ideal)")
+        print(" [WARN] (quite long, 5-15s is ideal)")
     else:
-        print(" ✓")
-    print(f"  Channels:       {'Stereo' if info['is_stereo'] else 'Mono'} {'⚠️  (will convert to mono)' if info['is_stereo'] else '✓'}")
-    print(f"  Max Amplitude:  {info['max_amplitude']:.3f} {'✓' if info['is_normalized'] else '⚠️  (low volume)'}")
+        print(" [OK]")
+    print(f"  Channels:       {'Stereo' if info['is_stereo'] else 'Mono'} {'[WARN] (will convert to mono)' if info['is_stereo'] else '[OK]'}")
+    print(f"  Max Amplitude:  {info['max_amplitude']:.3f} {'[OK]' if info['is_normalized'] else '[WARN] (low volume)'}")
     print(f"  RMS Level:      {info['rms_level']:.4f}")
     print(f"  Noise Floor:    {info['estimated_noise_floor']:.4f}")
     print(f"{'=' * 50}\n")