feat: deploy to Frostmoln production (#1019)

Moves the production deploy from AWS to the Frostmoln production cluster (namespace `schemas`).

- `deploy-prod` (AWS) has failed since CI left AWS (no `k8s.unbound.se` context on the runners). It's replaced by `deploy-prod-frostmoln`, as in unbound-site/lingonpaj-site: `deploy prod-frostmoln -n schemas` with the org's `FROSTMOLN_PRODUCTION_DEPLOY_KEY`, `FROSTMOLN_PRODUCTION_CLUSTER_ID` and `BUILDTOOLS_FROSTMOLN_PRODUCTION`.
- Restricted Pod Security: the image runs as `node` (uid 1000) with a matching securityContext. The service only writes under `/tmp` (cosmo composition).
- `secrets.yaml` (AWS ClusterSecretStore, RDS + CloudAMQP) → `secrets-prod-frostmoln.yaml`: the namespace's `frostmoln` SecretStore and the Frostmoln Secret `schemas` (`POSTGRES_URL`, `AMQP_URL`, `API_KEY`), written by infra's `seed-schemas.sh`. The file had no target suffix, so it applied to every target.
- `config-prod`/`pdb-prod` → `-prod-frostmoln`; the ALB ingress → a Traefik one for `/query` with a Let's Encrypt certificate.

Checked locally (amd64): runs as uid 1000 with all capabilities dropped, `wgc` works, `/tmp` writable; it fails only on the (dummy) database, as expected.

**Merge after** infra#1878 is applied and `seed-schemas.sh` + `migrate-schemas-db.sh` have run. `schemas.unbound.se` keeps pointing at AWS until the cut-over.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

https://claude.ai/code/session_01Ma8eHhW59hLAJuLzBnLvUu
Reviewed-on: #1019

.gitea/workflows/ci.yaml

@@ -83,16 +83,30 @@ jobs:
       - name: Build and push
         run: unset GITEA_TOKEN && build && push
 
-  deploy-prod:
+  deploy-prod-frostmoln:
     needs: build
     if: gitea.ref == 'refs/heads/main'
     runs-on: ubuntu-latest
     env:
-      BUILDTOOLS_CONTENT: ${{ secrets.BUILDTOOLS_CONTENT }}
+      BUILDTOOLS_CONTENT: ${{ secrets.BUILDTOOLS_FROSTMOLN_PRODUCTION }}
       GITEA_REPOSITORY: ${{ gitea.repository }}
+      FM_TENANT: 9ae61342-0f76-476f-8176-e46f6b0b0c32
     environment: prod
     steps:
       - uses: actions/checkout@v7
       - uses: buildtool/setup-buildtools-action@v1
-      - name: Deploy to production
-        run: deploy prod
+      - name: Install fm
+        run: |
+          sudo install -d -m 0755 /etc/apt/keyrings
+          sudo curl -fsSL -o /etc/apt/keyrings/frostmoln.gpg https://get.frostmoln.cloud/deb/frostmoln.gpg
+          sudo curl -fsSL -o /etc/apt/sources.list.d/frostmoln.sources https://get.frostmoln.cloud/deb/frostmoln.sources
+          sudo apt-get update && sudo apt-get install -y fm
+      - name: Deploy to Frostmoln production
+        env:
+          FROSTMOLN_API_KEY: ${{ secrets.FROSTMOLN_PRODUCTION_DEPLOY_KEY }}
+        # The cluster API is private: the kubeconfig's exec plugin opens an fm
+        # tunnel on demand. fm reads the key from its config file, not the env.
+        run: |
+          fm auth api-key set "$FROSTMOLN_API_KEY" > /dev/null
+          fm kubernetes cluster kubeconfig ${{ vars.FROSTMOLN_PRODUCTION_CLUSTER_ID }} --exec --file "$RUNNER_TEMP/kubeconfig"
+          KUBECONFIG_CONTENT="$(cat "$RUNNER_TEMP/kubeconfig")" deploy prod-frostmoln -n schemas