Fix: Add defensive checks to prevent tmux configuration for invalid users

- Modified 'roles/tmux/tasks/main.yml' to explicitly filter out
  the root directory ('/') as a valid home directory.
- Modified 'roles/tmux/tasks/tmux_config.yml' by adding a conditional
  check () to all tasks. This prevents the
  tasks from running for users with invalid home directories, which
  resolves the 'chown failed' error.

roles/tmux/tasks/main.yml

@@ -20,7 +20,7 @@
     - item.value[5] in ['/bin/bash', '/bin/zsh', '/usr/bin/bash', '/usr/bin/zsh', '/usr/bin/fish']
     - item.value[0] != 'root'
     - item.value[4] is defined
-    - item.value[4] | length > 1
+    - item.value[4] != '/'
 
 - name: Display the list of collected home directories
   ansible.builtin.debug: