[FEAT] Added --list-tracks option to display available tracks in media files

[tank0nf]

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This PR adds a new command-line option --list-tracks that allows users to list all available tracks in an input file and exit without processing the file for subtitle extraction.

When working with complex media files that contain multiple tracks, it's often difficult to know which track contains the subtitles you want to extract. This feature provides a simple way to explore the file structure before running a full extraction, making it easier to:

• Identify which streams contain subtitle data
• Determine the appropriate track numbers for extraction
• Save time by avoiding trial and error with multiple extraction attempts

Implementation

• Added a list_tracks_only flag to the options structure
• Implemented functionality to handle the flag in processing pipeline
• Added proper command-line argument handling in Rust wrapper
• Placed the option in the "Options that affect what will be processed" section

Example Usage

ccextractor video.mp4 --list-tracks

This will display information about available tracks in the file rather than extracting subtitles.

Testing

The feature has been tested with various media file formats including MP4, MKV, and TS files containing multiple subtitle tracks. It correctly lists available tracks and exits without performing extraction.
Distribution Used: Fedora Linux

TS Files:

MKV Files:

MP4 Files:

[tank0nf]

While working on the main functionality had to mess around with ccextractor.c a bit to implement the feature, added some minor indentation fixes were included to maintain consistent code style only in this file. The functional changes are focused on adding the --list-tracks option.