chore: normalize quote style in playbooks (#9)

## Summary
- Standardize single quotes to double quotes across deploy, destroy, provision, and restore playbooks

## Test plan
- No functional changes — formatting only

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Reviewed-on: #9
Co-authored-by: M.V. Hutz <git@maximhutz.me>
Co-committed-by: M.V. Hutz <git@maximhutz.me>

playbooks/restore.yml

@@ -43,7 +43,7 @@
       ansible.builtin.file:
         path: /root/restore
         state: directory
-        mode: '0777'
+        mode: "0777"
 
     - name: Extract backup.
       ansible.builtin.unarchive:
@@ -56,13 +56,13 @@
         remote_src: true
         src: /root/restore/backup/my-app-backup/
         dest: /root/data/
-        mode: '0777'
+        mode: "0777"
 
     - name: Update permissions.
       ansible.builtin.file:
         path: /root/data
         recurse: true
-        mode: '0777'
+        mode: "0777"
         owner: 1000
         group: 1000