update: Added Longhorn installation process and updated memory allocation for VMs

update: Added 'git' and 'vagrant' to required tools in pre-flight checks

fix: configured k3s install to use internal nic for flanel network

vagrant/dev/ubuntu/ansible/install_longhorn_prereqs.yaml

@@ -0,0 +1,47 @@
+---
+- name: Install k3s on 3-node cluster
+  hosts: vm1,vm2,vm3
+  become: true
+  become_user: root
+  serial: 1 # Ensure tasks are executed one host at a time
+  vars_files:
+    - vars.yaml
+
+  tasks:
+    - name: Install open-iscsi on all nodes
+      ansible.builtin.package:
+        name: open-iscsi
+        state: present
+        
+    - name: Install nfs-common on all nodes
+      ansible.builtin.package:
+        name: nfs-common
+        state: present
+
+    - name: Install cryptsetup and dmsetup packages
+      ansible.builtin.package:
+        name: 
+          - cryptsetup
+          - dmsetup
+        state: present
+        
+    - name: Load dm_crypt kernel module
+      community.general.modprobe:
+        name: dm_crypt
+        state: present
+      
+    - name: Make dm_crypt module load on boot
+      ansible.builtin.lineinfile:
+        path: /etc/modules
+        line: dm_crypt
+        create: yes
+        
+    - name: Check if dm_crypt module is loaded
+      ansible.builtin.shell: lsmod | grep dm_crypt
+      register: dm_crypt_check
+      failed_when: false
+      changed_when: false
+      
+    - name: Show dm_crypt status
+      ansible.builtin.debug:
+        msg: "dm_crypt module is {{ 'loaded' if dm_crypt_check.rc == 0 else 'not loaded' }}"