chore: remove old inventory for now and add vagrant

old inventory was never in use. Vagrant for local development

inventories/vagrant/host_vars/backend/keycloak.yml

@@ -0,0 +1 @@
+keycloak_admin_password: admin

inventories/vagrant/host_vars/backend/main.yml

@@ -0,0 +1,3 @@
+---
+# Backend server configuration
+# This server hosts application services that are exposed via the DMZ reverse proxy

inventories/vagrant/host_vars/backend/traefik.yml

@@ -0,0 +1,21 @@
+# Services to be exposed through the DMZ reverse proxy
+traefik_services:
+  - name: httpbin
+    domain: httpbin.local.test
+    port: 443
+    protocol: https
+  - name: keycloak
+    domain: keycloak.local.test
+    port: 443
+    protocol: https
+
+  # Example: Add more services as you deploy them
+  # - name: forgejo
+  #   domain: git.example.com
+  #   port: 3000
+  #   protocol: http
+
+  # - name: nextcloud
+  #   domain: cloud.example.com
+  #   port: 80
+  #   protocol: http