feat(poimen): publish the memory API at api-poimen.riotpiao.com

poimen-memory is a ClusterIP service on :8080, so a local pi session had no
route to the API. This adds an edge Ingress on the same nginx class and the
same Cloudflare-terminated shape as the frontend ingress.

Auth stays ZITADEL JWT (MEM_AUTH_MODE=jwt): a request without a valid bearer
token gets 401, so exposing the route does not expose the data.

Requires one Cloudflare proxied A record: api-poimen.riotpiao.com -> 192.168.1.160

k8s/apps/poimen-frontend/api-ingress.yaml

@@ -0,0 +1,38 @@
+---
+# Public entry point for the poimen-memory HTTP API.
+#
+# The API was reachable only inside the cluster (ClusterIP :8080), so a local pi
+# session had no way to use it. This Ingress exposes the same handler set the
+# in-cluster clients use: /mcp, /memory/*, /graphql, /health, /ready.
+#
+# Cloudflare terminates TLS in front of the nginx ingress, which is why this rule
+# carries no `tls:` section — the same shape as ingress.yaml next to it.
+#
+# Auth: poimen-memory validates ZITADEL JWTs (MEM_AUTH_MODE=jwt). A caller
+# without a valid bearer token gets 401, so exposing the route does not expose
+# the data.
+apiVersion: networking.k8s.io/v1
+kind: Ingress
+metadata:
+  name: poimen-api
+  namespace: poimen
+  annotations:
+    # MCP calls and ingest can be slow; the provider may stream. Match the
+    # frontend ingress so a long tool call is not cut at 60s.
+    nginx.ingress.kubernetes.io/proxy-read-timeout: "3600"
+    nginx.ingress.kubernetes.io/proxy-send-timeout: "3600"
+    nginx.ingress.kubernetes.io/proxy-buffering: "off"
+    nginx.ingress.kubernetes.io/proxy-body-size: "50m"
+spec:
+  ingressClassName: nginx
+  rules:
+    - host: api-poimen.riotpiao.com
+      http:
+        paths:
+          - path: /
+            pathType: Prefix
+            backend:
+              service:
+                name: poimen-memory
+                port:
+                  number: 8080

k8s/apps/poimen-frontend/kustomization.yaml

@@ -6,3 +6,5 @@ kind: Kustomization
 # riotpiao-poimen/poimen-frontend.git k8s/ — each repo owns its own k8s.
 resources:
   - ingress.yaml
+  # The memory API. Without it a local pi session has no route to :8080.
+  - api-ingress.yaml