fix: add request_upgrades.py to image, add web dashboard

- Dockerfile: add COPY for request_upgrades.py (was missing — root cause
  of Monday upgrade CronJob failing with 'No such file'), add git (needed
  for repo cloning in upgrade workflow), copy web.py + templates/
- requirements.txt: add fastapi, uvicorn, jinja2 for web dashboard
- web.py: FastAPI dashboard with image inventory and upgrade trigger pages
- templates/: base layout, images page (namespace→app→container grouped
  with live version status), upgrade page (outdated list + trigger button
  + job history)
- kubernetes/web-deployment.yaml: Deployment + LoadBalancer at 192.168.87.13
- kubernetes/rbac.yaml: add version-tracker-web ServiceAccount, ClusterRole
  (read pods/deployments/replicasets/statefulsets/daemonsets/jobs/cronjobs),
  and namespace Role to create upgrade Jobs
- kubernetes/upgrade-cronjob.yaml: fix YAML indentation bug on GITEA_USERNAME
  and GITEA_COMMITTER_NAME env vars

requirements.txt

@@ -1,3 +1,6 @@
 kubernetes==29.0.0
 requests==2.32.3
 packaging==24.2
+fastapi==0.115.6
+uvicorn[standard]==0.32.1
+jinja2==3.1.4