Bump remaining apps: major version slots and infrastructure

New version slots (major version jumps):
- gitea: 1.24.3 -> 28.2.0 (slot 1 -> 28)
- ghost: 5.130.6 -> 6.72.0 (slot 5 -> 6)
- formbricks: 3.6.0 -> 6.1.0 (slot 3 -> 6)
- mattermost: 10.8.1 -> 12.0.1 (slot 10 -> 12)
- zulip: 9.4 -> 12.3 (slot 9 -> 12)
- immich: 1.135.3 -> 3.3.5 (slot 1 -> 3)
- openproject: 16.1.1 -> 17.9.3 (slot 16 -> 17)
- listmonk: 5.0.3 -> 6.1.0 (slot 5 -> 6)
- discourse: 3.5.3 -> 2026.10.0 (slot 3 -> 2026, calver)

Same-slot large bumps:
- vllm: 0.9.2 -> 0.32.0
- longhorn: v1.8.1 -> v1.13.0

Infrastructure:
- cert-manager: v1.17.2 -> v1.21.2
- coredns: v1.12.0 -> v1.14.7
- externaldns: v0.13.4 -> v0.23.0
- metallb: v0.15.0 -> v0.16.1
- mysql: 9.1.0 -> 9.7.4
- node-feature-discovery: v0.17.3 -> v0.20.1
- nvidia-device-plugin: v0.17.1 -> v0.20.1

ghost/versions/6/deployment.yaml

@@ -0,0 +1,105 @@
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: ghost
+  namespace: {{ .namespace }}
+spec:
+  replicas: 1
+  strategy:
+    type: Recreate
+  selector:
+    matchLabels:
+      component: web
+  template:
+    metadata:
+      labels:
+        component: web
+    spec:
+      securityContext:
+        runAsNonRoot: true
+        runAsUser: 1000
+        runAsGroup: 1000
+        fsGroup: 1000
+        seccompProfile:
+          type: RuntimeDefault
+      containers:
+        - name: ghost
+          image: ghost:6.72.0-alpine
+          ports:
+            - name: http
+              containerPort: 2368
+              protocol: TCP
+          env:
+            - name: NODE_ENV
+              value: production
+            - name: url
+              value: "https://{{ .domain }}"
+            - name: database__client
+              value: mysql
+            - name: database__connection__host
+              value: "{{ .db.host }}"
+            - name: database__connection__port
+              value: "{{ .db.port }}"
+            - name: database__connection__database
+              value: "{{ .db.name }}"
+            - name: database__connection__user
+              value: "{{ .db.user }}"
+            - name: database__connection__password
+              valueFrom:
+                secretKeyRef:
+                  name: ghost-secrets
+                  key: dbPassword
+            - name: mail__transport
+              value: SMTP
+            - name: mail__options__host
+              value: "{{ .smtp.host }}"
+            - name: mail__options__port
+              value: "{{ .smtp.port }}"
+            - name: mail__options__auth__user
+              value: "{{ .smtp.user }}"
+            - name: mail__options__auth__pass
+              valueFrom:
+                secretKeyRef:
+                  name: ghost-secrets
+                  key: smtpPassword
+            - name: mail__from
+              value: "{{ .smtp.from }}"
+          resources:
+            limits:
+              cpu: 1000m
+              ephemeral-storage: 2Gi
+              memory: 512Mi
+            requests:
+              cpu: 50m
+              ephemeral-storage: 50Mi
+              memory: 256Mi
+          volumeMounts:
+            - name: ghost-data
+              mountPath: /var/lib/ghost/content
+          livenessProbe:
+            httpGet:
+              path: /ghost/api/admin/site/
+              port: 2368
+            initialDelaySeconds: 120
+            timeoutSeconds: 5
+            periodSeconds: 30
+            failureThreshold: 6
+          readinessProbe:
+            httpGet:
+              path: /ghost/api/admin/site/
+              port: 2368
+            initialDelaySeconds: 60
+            timeoutSeconds: 5
+            periodSeconds: 15
+            failureThreshold: 3
+          securityContext:
+            allowPrivilegeEscalation: false
+            capabilities:
+              drop:
+                - ALL
+            readOnlyRootFilesystem: false
+      volumes:
+        - name: ghost-data
+          persistentVolumeClaim:
+            claimName: ghost-data
+      restartPolicy: Always