ci: deploy :latest with rollout restart, single replica

Drop the sha-pinned overlay and automatic rollback. The deployment now
runs 1 replica with imagePullPolicy Always, and CI restarts it after
apply so the new :latest image is pulled.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

k8s/kustomization.yaml

@@ -15,7 +15,7 @@ labels:
       app.kubernetes.io/name: personal-site
       app.kubernetes.io/managed-by: kustomize
 
-# CI pins the tag to sha-<commit> via a generated overlay (see deploy.yml).
+# CI deploys :latest and runs `kubectl rollout restart` to pick up the new image.
 images:
   - name: jesseinit-portfolio
     newName: tea.jesseinit.dev/jesseinit/personal-site