Docs: rename installer to usb installer

docs/mkdocs.yml

@@ -49,7 +49,7 @@ nav:
   - Guides:
       - Getting Started:
           - Creating Your First Clan: guides/getting-started/index.md
-          - Create Installer (optional): guides/getting-started/installer.md
+          - Create USB Installer (optional): guides/getting-started/installer.md
           - Add Machines: guides/getting-started/add-machines.md
           - Secrets & Facts: guides/getting-started/secrets.md
           - Deploy Machine: guides/getting-started/deploy.md

docs/site/guides/getting-started/installer.md

@@ -1,4 +1,4 @@
-# Clan Installer Image for Physical Machines (optional)
+# USB Installer Image for Physical Machines (optional)
 
 To install Clan on physical machines, you need to use our custom installer image. This is necessary for proper installation and operation.