Fix UUID cast in task creation, add kind test manifests

- Fix parent_task_id NULLIF cast to UUID type in INSERT query
- Fix itoa helper to use strconv.Itoa
- Handle AddReaction errors gracefully in webhook handler
- Add hack/kind/ manifests for local testing with kind cluster

hack/kind/manifests/rbac.yaml

@@ -0,0 +1,40 @@
+---
+apiVersion: v1
+kind: ServiceAccount
+metadata:
+  name: forgebot-operator
+  namespace: forgebot
+---
+apiVersion: rbac.authorization.k8s.io/v1
+kind: ClusterRole
+metadata:
+  name: forgebot-operator
+rules:
+  - apiGroups: ["forgebot.unkin.net"]
+    resources: ["*"]
+    verbs: ["*"]
+  - apiGroups: ["forgebot.unkin.net"]
+    resources: ["*/status"]
+    verbs: ["get", "update", "patch"]
+  - apiGroups: ["batch"]
+    resources: ["jobs"]
+    verbs: ["get", "list", "watch", "create", "delete"]
+  - apiGroups: [""]
+    resources: ["pods", "configmaps", "secrets", "events", "serviceaccounts"]
+    verbs: ["get", "list", "watch"]
+  - apiGroups: ["coordination.k8s.io"]
+    resources: ["leases"]
+    verbs: ["get", "list", "watch", "create", "update", "patch", "delete"]
+---
+apiVersion: rbac.authorization.k8s.io/v1
+kind: ClusterRoleBinding
+metadata:
+  name: forgebot-operator
+subjects:
+  - kind: ServiceAccount
+    name: forgebot-operator
+    namespace: forgebot
+roleRef:
+  apiGroup: rbac.authorization.k8s.io
+  kind: ClusterRole
+  name: forgebot-operator