cleanup: remove dead code and duplicate docs

- Remove session-ses_2f27.md (161KB raw session log)
- Remove 49 ROOT_* duplicate files across REFERENCE/
- Remove 14 duplicate files between REFERENCE/ root and history/
- Remove asr_legacy.rs (dead code, replaced by asr.rs)
- Remove src/core/worker/ (duplicate JobWorker)
- Remove src/core/layers/ (empty directory)
- Remove 4 .bak files in src/
- Remove 7 dead private methods in worker/processor.rs
- Remove backup directory from git tracking

scripts/test_pyannote_audio.py

@@ -6,7 +6,6 @@ pyannote.audio 測試腳本
 
 import sys
 import json
-import os
 
 def test_pyannote(audio_path, output_path):
     """測試 pyannote.audio 說話人分離"""
@@ -47,13 +46,13 @@ def test_pyannote(audio_path, output_path):
         with open(output_path, "w") as f:
             json.dump(result, f, indent=2)
         
-        print(f"\n=== 測試結果 ===")
+        print("\n=== 測試結果 ===")
         print(f"說話人數量：{result['num_speakers']}")
         print(f"片段數量：{len(segments)}")
         print(f"輸出檔案：{output_path}")
         
         # 顯示前 5 段
-        print(f"\n前 5 段：")
+        print("\n前 5 段：")
         for i, seg in enumerate(segments[:5], 1):
             print(f"  {i}. [{seg['start']:.2f}s - {seg['end']:.2f}s] {seg['speaker']}")