feat: migrate to Gitea, productize Helm chart, unify version

- CI: replace GitLab pipeline with Gitea Actions (.gitea/workflows/release.yaml);
  publish .deb/image/hosted/chart to Gitea registries; gate image+hosted on .deb
  (needs + registry pre-check)
- drop connectone/Nexus; apt now from the Gitea Debian registry
- single version source (/VERSION=3.2.8); CI enforces .env/Chart consistency
- restructure: build/->packaging/deb, root Dockerfile->packaging/image,
  hosted/->packaging/hosted, .kube/->charts/freeradius
- Helm chart: documented values, DB password via Secret/$ENV, configurable
  scheduling/persistence; remove plaintext creds and hostPath PV
- gitignore *.env_cnf; docs for hosted (RU)/helm/root + agent KB sync

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

packaging/image/local-noble.list

@@ -0,0 +1,13 @@
+Types: deb
+URIs: http://ru.archive.ubuntu.com/ubuntu/
+Suites: noble noble-updates noble-backports
+Components: main universe restricted multiverse
+Signed-By: /usr/share/keyrings/ubuntu-archive-keyring.gpg
+
+## Ubuntu security updates. Aside from URIs and Suites,
+## this should mirror your choices in the previous section.
+Types: deb
+URIs: http://ru.archive.ubuntu.com/ubuntu/
+Suites: noble-security
+Components: main universe restricted multiverse
+Signed-By: /usr/share/keyrings/ubuntu-archive-keyring.gpg