Filter Zoekt exact code search results by repository
### Proposal
Zoekt code search currently does not allow to search for repositories.
Previously it was possible to search with something like `path:*-ops/config/*` finding all projects ending with `-ops` with a `config` folder, this is currently not posisble.
The suggestion is to implement the `r:` / `repo:` option available in Zoekt - https://github.com/sourcegraph/zoekt/blob/main/web/templates.go#L173
### Context
- https://github.com/sourcegraph/zoekt/blob/main/cmd/zoekt-git-index/main.go#L115
- https://github.com/sourcegraph/zoekt/pull/521/files
### Release notes
You can now filter exact code search results by repository using the `repo:` (or `r:`) syntax in GitLab's Zoekt-powered code search. This allows you to scope your search to specific repositories or repository patterns directly from the search query, without relying on project-level navigation.
For example, searching for `def authenticate repo:my-group/my-project` returns results only from that repository. You can also use partial paths or patterns to match multiple repositories.
issue