feat: Add tag support to file history display

- Modified cvs_client.py get_file_history() to parse and extract tags from CVS log
- Updated ui.js displayHistory() to render tags for each revision
- Added CSS styling for history tags with proper theming support
- Tags are displayed inline with revision information in history view

ui/ui.js

@@ -244,6 +244,7 @@ class UIManager {
                 <div class="history-log-section">
                     <div class="history-log">${revision.log ? this.escapeHtml(revision.log) : ''}</div>
                     ${revision.state && revision.state !== 'Exp' ? `<span class="history-state">${revision.state}</span>` : ''}
+                    ${revision.tags && revision.tags.length > 0 ? `<span class="history-tags">${revision.tags.map(tag => `<span class="history-tag">${this.escapeHtml(tag)}</span>`).join('')}</span>` : ''}
                 </div>
                 <div class="history-author">${revision.author || 'Unknown'}</div>
                 <div class="history-date" title="${revision.date || 'N/A'}">${this.getRelativeDate(revision.date) || 'N/A'}</div>