feat: tags and their subdirectories can be fetched

[jpotw]

Additional Features Building on #203 (See #203)
(I can make a new PR if you confirm and merge #203)

This PR extends the previous work by adding support for fetching and recognizing tags, along with their subdirectories.
(history: #196)

Features:

• Tag Options for CLI: Added --tag and -t flags.
  • If both branch and tag names are specified, the process will abort to avoid confusion.
• Tag Fetching: Now fetches repository tags in addition to branches.
  • Branch names take priority over tag names to handle cases where they’re names are identical. (This logic could be revisited in future updates if needed.)
• Tests: Added new test cases to cover the changes.
• Miscellaneous: Includes some minor tweaks to satisfy pre-commit checks.

Examples

Web Interface

CLI Examples

❯ gitingest /~https://github.com/cyclotruc/gitingest/tree/v0.1.3/src/gitingest
Analysis complete! Output written to: digest.txt

Summary:
Repository: cyclotruc/gitingest
Tag: v0.1.3
Subpath: /src/gitingest
Files analyzed: 11

Estimated tokens: 16.5k

❯ gitingest /~https://github.com/pytorch/pytorch/tree/v2.4.1/torch/distributed/elastic
Analysis complete! Output written to: digest.txt

Summary:
Repository: pytorch/pytorch
Tag: v2.4.1
Subpath: /torch/distributed/elastic
Files analyzed: 47

Estimated tokens: 79.0k