feat: add batch import for bulk scrobbling

[dotMavriQ]

Description

Adds bulk import functionality to scrobble multiple tracks at once from a file.

Changes

• New batch module supporting CSV and JSON formats
• --import <file> flag to import scrobbles from file
• --create-import flag to generate example import files
• Rate limiting (1 second delay between scrobbles to respect API limits)
• Automatic stats and history recording for imported tracks
• Confirmation prompt before starting import
• Progress indicator showing success/failure per track

File Formats

CSV Format

artist,title,album,timestamp
Pink Floyd,Comfortably Numb,The Wall,
Led Zeppelin,Stairway to Heaven,Led Zeppelin IV,

JSON Format

[
  {"artist": "Pink Floyd", "title": "Comfortably Numb", "album": "The Wall"},
  {"artist": "Led Zeppelin", "title": "Stairway to Heaven", "album": "Led Zeppelin IV"}
]

Testing

• CSV import tested
• JSON import tested
• Rate limiting verified
• Stats recording verified

Type of Change

• New feature (non-breaking change which adds functionality)