Fix prolly-ui commit data extraction and improve UI styling

[zhangfengcdt]

This PR fixes a critical bug in the prolly-ui tool where modified entries were not being displayed in commit details, and improves the overall UI styling for better usability.

Bug Fix

• Fixed missing modified entries: The parser was only handling added ([32m+) and removed ([31m-)
  entries but failed to parse modified entries ([33m~) from git-prolly show output
• Updated parser logic: Added support for the yellow tilde format [33m~ key = "old" -> "new"[0m in
  parse_prolly_show_output()
• Resolved data inconsistency: Fixed inconsistent data extraction between dataset-specific and git
  repository commit structures

UI Improvements

• Redesigned tags: Changed dataset tags from blue pill-shaped buttons to subtle gray tags with
  non-clickable appearance
• Styled repository path: Converted plain text path to a subtle monospace tag
• Improved layout: Moved dataset tags inline with repository path for better space utilization
• Enhanced visual hierarchy: Used consistent styling with light backgrounds, subtle borders, and
  appropriate spacing

Technical Details

• Modified src/bin/prolly-ui.rs parser to handle all three git-prolly output formats
• Updated CSS styling for .dataset-tag, .repository-path, and new .repo-and-datasets wrapper
• Maintained responsive design with flexbox and wrap capabilities
• Added cursor: default to indicate non-interactive elements

Test Plan

• Verified modified entries now appear correctly in commit details
• Tested with multi-dataset repositories across different branches
• Confirmed UI styling works across different screen sizes
• Validated that all commit types (add/modify/remove) display properly