Fix ansible_user undefined error in GKE and AKS Terraform tasks (#189)

When ansible_connection=local is used, ansible_user is never set and
referencing it causes an immediate failure. Replace /home/{{ ansible_user }}
with {{ ansible_env.HOME }} which resolves correctly in local connections.

Co-authored-by: Claude Sonnet 4.6 (1M context) <noreply@anthropic.com>

Author: ssimpson89

playbooks/roles/k8s_setup/tasks/k8s_setup_aks.yml

@@ -76,7 +76,7 @@
         project_path: "{{ playbook_dir }}/../ascender_install_artifacts/aks_deploy"
         state: present
         variables:
-          home_dir: "/home/{{ ansible_user}}"
+          home_dir: "{{ ansible_env.HOME }}"
           aks_cluster_name: "{{ AKS_CLUSTER_NAME }}"
           resource_group_location: "{{ AKS_CLUSTER_REGION }}"
           node_count: "{{ AKS_NUM_WORKER_NODES }}"

playbooks/roles/k8s_setup/tasks/k8s_setup_gke.yml

@@ -84,7 +84,7 @@
         project_path: "{{ playbook_dir }}/../ascender_install_artifacts/gke_deploy"
         state: present
         variables:
-          home_dir: "/home/{{ ansible_user}}"
+          home_dir: "{{ ansible_env.HOME }}"
           gke_cluster_name: "{{ GKE_CLUSTER_NAME }}"
           kubernetes_version: "{{ GKE_K8S_VERSION }}"
           project_id: "{{ GKE_PROJECT_ID }}"