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.

argocd/projects/aitooling.yaml

@@ -0,0 +1,19 @@
+---
+apiVersion: argoproj.io/v1alpha1
+kind: AppProject
+metadata:
+  name: aitooling
+  namespace: argocd
+spec:
+  description: AI tooling services
+  sourceRepos:
+    - https://git.unkin.net/unkin/argocd-apps
+  destinations:
+    - namespace: 'litellm'
+      server: https://kubernetes.default.svc
+  clusterResourceWhitelist:
+    - group: ''
+      kind: Namespace
+  namespaceResourceWhitelist:
+    - group: '*'
+      kind: '*'