Target shared docker runners in scheduled-deploy

The instance runners advertise `dind`/`docker` labels, not `ubuntu-latest`, so
the job sat queued unmatched. Point runs-on at `docker`.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

.gitea/workflows/scheduled-deploy.yml

@@ -7,9 +7,8 @@
 # pings the deploy hook.
 #
 # Setup (once):
-#   - A Gitea Actions runner must be registered and online for this repo/org,
-#     advertising a label that matches `runs-on` below (default act_runner maps
-#     `ubuntu-latest`; change it if your runner uses a different label).
+#   - Uses the shared `docker`-labelled runners. If those labels change, update
+#     `runs-on` below to match a runner that is online.
 #   - Add a repo secret COOLIFY_DEPLOY_HOOK = the app's deploy URL from Coolify
 #     (app → Webhooks → "Deploy Webhook", e.g.
 #     https://coolify.example.com/api/v1/deploy?uuid=<uuid>&force=false).
@@ -31,7 +30,7 @@ on:
 
 jobs:
   trigger-deploy:
-    runs-on: ubuntu-latest
+    runs-on: docker
     steps:
       - name: Ping Coolify deploy hook
         env: