Show tag names in git blame tooltips

[pixel365]

Objective

Show git tag names in git: blame commit details.

Solution

Fetch tag names for commits included in blame data and pass them through the blame rendering path. Render tag names as chips in the blame hover
tooltip and expanded blame popover.

Tag lookup is best-effort, so blame still renders if tag lookup fails.

Testing

• cargo test -p git test_parse_tag_names_for_lightweight_and_annotated_tags
• cargo check -p git_ui
• cargo check -p editor
• cargo check -p project

Manual testing:

• Opened git: blame on a file with a tagged commit.
• Verified tag chips are shown in the blame hover tooltip and expanded popover.

Self-Review Checklist:

• I've reviewed my own diff for quality, security, and reliability
• Unsafe blocks (if any) have justifying comments
• The content adheres to Zed's UI standards (UX/UI and [icon]
  (https://github.com/zed-industries/zed/blob/main/crates/icons/README.md) guidelines)
• Tests cover the new/changed behavior
• Performance impact has been considered and is acceptable

Showcase

Before:

After: