[BUG]: No "no results" message shown when filters match zero repositories

### Bug Description

When search or filter selections on the Repository Explorer page match zero repositories, the table renders with only the header row and no rows underneath there is no message telling the user that no repositories matched their filters. The empty state component only triggers when the organization has zero repositories overall, not when
a filter simply returns zero matches from a non-empty repository list.

### Steps to Reproduce

1. Go to the Repositories page for any organization with repositories
2. Type a search term that won't match any repository name or description (e.g. "xyz")
3. See the repository count update to "0 / 442 repos" (or similar)
4. Notice the table shows only the header row, with a blank area underneath and no explanation

### Logs and Screenshots

Screenshot attached: searching "xyz" shows "0 / 442 repos" in the header, but the table body is completely empty with no "no results" message.

## screenshot

### Environment Details

- OS: Windows 11 / macOS / Linux
- Browser: Chrome 120 / Firefox / Safari
- Relevant file: src/pages/RepositoriesPage.jsx

### Impact

Critical - Application is unusable

### Code of Conduct

- [x] I have joined the [Discord server](https://discord.gg/hjUhu33uAn) and will post updates there
- [x] I have searched existing issues to avoid duplicates

Open src/pages/RepositoriesPage.jsx and reproduce the issue by searching for “xyz” on an organization with repositories. Trace the existing empty-state condition for zero repositories versus zero filtered matches. Done means the Repository Explorer shows a clear no-results message when filters match zero repositories while retaining the existing state for organizations with no repositories.

索引モデルが issue の本文から書いたものです。