feat(links): add deep linking support

[CalvinAllen]

Description

Add deep linking functionality to generate and handle shareable links that open specific locations in VS GitRanger, enabling easy sharing of code references with teammates.

Features

Generate Deep Links To

• Specific files at revision
• Specific lines in files
• Commits
• Branches
• Tags
• Comparisons (branch vs branch)
• Repository views
• Search results

Link Formats

• VS GitRanger protocol links (vsgitranger://...)
• Web links (for remote providers)
• Clipboard-friendly format

Copy Link Commands

• Copy link to current file
• Copy link to current line(s)
• Copy link to commit
• Copy link to branch
• Copy link to comparison
• Context menu integration

Handle Incoming Links

• Register protocol handler
• Parse and navigate to linked location
• Open appropriate view/editor
• Handle missing references gracefully

Link Content

vsgitranger://open?repo=<path>&file=<path>&line=<num>&ref=<sha>
vsgitranger://compare?repo=<path>&from=<ref>&to=<ref>
vsgitranger://commit?repo=<path>&sha=<sha>

Configuration Options

• Default link format preference
• Include line numbers by default
• Protocol handler registration
• Web link provider preference

Acceptance Criteria

• Deep links can be generated for all supported targets
• Links copy to clipboard correctly
• Protocol handler opens VS and navigates correctly
• Invalid/broken links handled gracefully
• Context menu options work in all views