chore(paperclip): Remove legacy plain Ingress for paperclip.basicstack.de (DEV-456)

Pangolin's IngressRoute 1-paperclip-router (pangolin ns) now owns the
paperclip.basicstack.de route (SSO gate via badger middleware). The legacy
Ingress at paperclip/paperclip bypassed Pangolin entirely and produced
"secret paperclip/paperclip-tls does not exist" noise in Traefik.

Cluster deletion follows in this heartbeat; Argo sync policy has no
automated prune, so removal from source is safe first.

Co-Authored-By: Paperclip <noreply@paperclip.ing>

apps/paperclip/ingress.yaml

@@ -1,25 +0,0 @@
-apiVersion: networking.k8s.io/v1
-kind: Ingress
-metadata:
-  name: paperclip
-  namespace: paperclip
-  annotations:
-    cert-manager.io/cluster-issuer: letsencrypt-prod
-    traefik.ingress.kubernetes.io/router.entrypoints: web,websecure
-spec:
-  ingressClassName: traefik
-  rules:
-  - host: paperclip.basicstack.de
-    http:
-      paths:
-      - path: /
-        pathType: Prefix
-        backend:
-          service:
-            name: paperclip
-            port:
-              number: 3100
-  tls:
-  - hosts:
-    - paperclip.basicstack.de
-    secretName: paperclip-tls