feat: poimen-toolkit ArgoCD app + sourceRepo

- k8s/argocd/apps/71-poimen-toolkit.yaml: Application wave-7, points to
  poimen-toolkit repo k8s/ path, ServerSideApply for CRD schema size,
  image-updater for controller:latest digest
- k8s/argocd/projects/homelab-project.yaml: add poimen-toolkit.git to sourceRepos

k8s/argocd/apps/71-poimen-toolkit.yaml

@@ -0,0 +1,34 @@
+apiVersion: argoproj.io/v1alpha1
+kind: Application
+metadata:
+  name: poimen-toolkit
+  namespace: argocd
+  annotations:
+    argocd.argoproj.io/sync-wave: "7"
+    argocd-image-updater.argoproj.io/image-list: |
+      controller=ghcr.io/riotpiao-poimen/poimen-toolkit-controller
+    argocd-image-updater.argoproj.io/controller.update-strategy: digest
+    argocd-image-updater.argoproj.io/controller.allow-tags: regexp:^latest$
+    argocd-image-updater.argoproj.io/write-back-method: argocd
+spec:
+  project: homelab
+  source:
+    repoURL: https://forgejo.riotpiao.com/riotpiao-poimen/poimen-toolkit.git
+    targetRevision: main
+    path: k8s
+  destination:
+    server: https://kubernetes.default.svc
+    namespace: poimen
+  syncPolicy:
+    automated:
+      prune: true
+      selfHeal: true
+    syncOptions:
+      - CreateNamespace=true
+      - ServerSideApply=true
+    retry:
+      limit: 5
+      backoff:
+        duration: 5s
+        factor: 2
+        maxDuration: 3m