feat(paperless): add paperless-ai with local LLM for auto-tagging

- paperless-ai deployment using clusterzx/paperless-ai
- LLM via local api-gateway (reasoning model, no auth - phase 3 pending)
- Paperless API token SOPS-encrypted
- Auto-tags new documents, 5min scan interval
- Adds 'ai-processed' tag to classified documents

k8s/apps/paperless/kustomization.yaml

@@ -11,6 +11,7 @@ resources:
   - backup-cronjob.yaml
   - adapter-configmap.yaml
   - rbac.yaml
+  - paperless-ai.yaml
 # postgres: paperless-db CNPG Cluster, deployed by k8s/infra/databases (wave 2,
 # before this app at wave 8) - not duplicated here. Same for the paperless-oidc
 # and paperless-minio-creds Secrets, written by PostSync provisioning Jobs in

k8s/apps/paperless/paperless-ai.yaml

@@ -0,0 +1,62 @@
+# Secret paperless-ai-config managed via SOPS (argocd/secrets/paperless-ai-secrets.enc.yaml)
+---
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: paperless-ai
+  namespace: paperless
+  labels:
+    app.kubernetes.io/name: paperless-ai
+spec:
+  replicas: 1
+  selector:
+    matchLabels:
+      app.kubernetes.io/name: paperless-ai
+  template:
+    metadata:
+      labels:
+        app.kubernetes.io/name: paperless-ai
+    spec:
+      tolerations:
+        - key: node-role.kubernetes.io/control-plane
+          operator: Exists
+          effect: NoSchedule
+      containers:
+        - name: paperless-ai
+          image: clusterzx/paperless-ai:latest
+          env:
+            # Paperless-ngx connection
+            - name: PAPERLESS_API_URL
+              value: "http://paperless.paperless.svc.cluster.local:8000"
+            - name: PAPERLESS_API_TOKEN
+              valueFrom:
+                secretKeyRef:
+                  name: paperless-ai-config
+                  key: PAPERLESS_API_TOKEN
+            # LLM API — local gateway, no auth required (phase 3 not built yet)
+            - name: AI_PROVIDER
+              value: "custom"
+            - name: CUSTOM_BASE_URL
+              value: "http://api-gateway.api.svc.cluster.local:8080/v1"
+            - name: CUSTOM_API_KEY
+              value: "not-required"
+            - name: CUSTOM_MODEL
+              value: "reasoning"
+            # Behavior
+            - name: SCAN_INTERVAL
+              value: "300"
+            - name: PROCESS_PREDEFINED_DOCUMENTS
+              value: "no"
+            - name: ADD_AI_TAG
+              value: "yes"
+            - name: AI_TAG_NAME
+              value: "ai-processed"
+            - name: USE_PROMPT_TAGS
+              value: "yes"
+          resources:
+            requests:
+              cpu: 50m
+              memory: 128Mi
+            limits:
+              cpu: 500m
+              memory: 512Mi