feat(ops/monorepo-gerrit): link r/<id> shortlinks to revisions

I've decided to use the commit view instead of the log view (which cgit
uses) for now. It really depends on how you use it in commit messages:
To refer to a depot state or to a specific change (independently of what
CL gerrit assigned). I'm happy to change it to use the log view.

Change-Id: I472b511fa1322f91304f6543473b51f9c5f21ca2
Reviewed-on: https://cl.tvl.fyi/c/depot/+/12837
Autosubmit: sterni <sternenseemann@systemli.org>
Reviewed-by: tazjin <tazjin@tvl.su>
Tested-by: BuildkiteCI

ops/modules/monorepo-gerrit.nix

@@ -97,6 +97,12 @@ in
         link = "https://cl.tvl.fyi/$1";
       };
 
+      # Auto-link links to monotonically increasing revisions/commits
+      commentlink.revision = {
+        match = "r/(\\d+)";
+        link = "https://code.tvl.fyi/commit/?h=refs/r/$1";
+      };
+
       # Configures integration with Keycloak, which then integrates with a
       # variety of backends.
       auth.type = "OAUTH";