feat: add options for branch, local_backend, and publish_mode (editorial flow)

Example for a YAML config:

```
  cms:
    branch: main
    local_backend: true
    publish_mode:
 ```

Close #2124

test/content/admin/index.md

@@ -0,0 +1,7 @@
+---
+# Generate Wowchemy CMS
+type: wowchemycms
+outputs:
+  - wowchemycms_config
+  - HTML
+---

test/content/home/section.md

@@ -1,5 +1,6 @@
 ---
 widget: blank
+widget_id: hello
 headless: true
 weight: 1
 design: