feat: add litellm to new aitooling ArgoCD project

Deploys LiteLLM proxy with CNPG PostgreSQL (3-instance HA), PgBouncer
pooler, and Redis cache. Introduces a dedicated aitooling AppProject and
ApplicationSet to keep AI tooling services separate from platform infra.

apps/base/litellm/services.yaml

@@ -0,0 +1,34 @@
+---
+apiVersion: v1
+kind: Service
+metadata:
+  name: litellm
+  namespace: litellm
+spec:
+  internalTrafficPolicy: Cluster
+  ports:
+    - name: http
+      port: 4000
+      protocol: TCP
+      targetPort: http
+  selector:
+    app: litellm
+  sessionAffinity: None
+  type: ClusterIP
+---
+apiVersion: v1
+kind: Service
+metadata:
+  name: redis-service
+  namespace: litellm
+spec:
+  internalTrafficPolicy: Cluster
+  ports:
+    - name: redis
+      port: 6379
+      protocol: TCP
+      targetPort: redis
+  selector:
+    app: redis
+  sessionAffinity: None
+  type: ClusterIP