Icon request: tab group search

### Icon Request: tab_group_search

**Problem Statement**
Currently, it's not possible to search tab groups, only scrolling is available.

**Icon Description**
- `tab_group` icon + `search` magnifying glass.

**Search Keywords**
tab group search

**Similar Existing Icons**
- `tab_search` -- designed specifically for tab search, but the `manage_search` icon is used instead of it (visible in the vertical tabs mode)

Start by reviewing the existing tab_group and search icons, then compare the tab_search and manage_search examples mentioned in the issue. Add a tab_group_search icon matching the requested combination and verify that its search keywords are included with the icon assets.

Written by the indexing model from the issue text.