Fix discourse, moodle, supabase upgrades

- discourse 2026.10.0: skip assets:precompile in init container
  (assets are pre-built in 2026.x images, no git repo present)
  Re-enable slot 2026 as latest
- moodle: migrate from bitnamilegacy/moodle (EOL Aug 2025) to
  oksigenia/moodle:4.5 (drop-in replacement, same env vars/volumes,
  weekly rebuilds with PHP patches)
- supabase: bump all 7 components to self-hosted v0.8.3 tags
  (studio, gotrue, postgrest, realtime, storage-api, postgres-meta, kong)

discourse/app.yaml

@@ -3,4 +3,4 @@ is: discourse
 description: Discourse is a modern, open-source discussion platform designed for online communities and forums.
 category: community
 icon: https://cdn.jsdelivr.net/gh/homarr-labs/dashboard-icons/svg/discourse.svg
-latest: "3"
+latest: "2026"

discourse/versions/2026/deployment.yaml

@@ -49,9 +49,7 @@ spec:
               set -e
               cd /var/www/discourse
               export HOME=/root
-              git config --global --add safe.directory /var/www/discourse
               bundle exec rake db:migrate
-              bundle exec rake assets:precompile
           env:
             - name: RAILS_ENV
               value: "production"