feat(home): add compact home page preset to avoid abuse classification

- Add compact_home_enabled setting to provide a minimal landing page
- Preserves custom home_content priority over compact mode
- Renders only site identity, navigation, and login/dashboard link
- Avoids marketing copy that triggers anti-fraud systems
- Includes focused backend/frontend tests and i18n support

Fixes #5065

frontend/src/components/auth/__tests__/WechatOAuthSection.spec.ts

@@ -73,6 +73,7 @@ function buildPublicSettings(overrides: Partial<WeChatPublicSettings> = {}): WeC
     contact_info: '',
     doc_url: '',
     home_content: '',
+    compact_home_enabled: false,
     hide_ccs_import_button: false,
     payment_enabled: false,
     table_default_page_size: 20,

frontend/src/components/user/profile/__tests__/ProfileIdentityBindingsSection.spec.ts

@@ -250,6 +250,7 @@ describe('ProfileIdentityBindingsSection', () => {
       contact_info: '',
       doc_url: '',
       home_content: '',
+      compact_home_enabled: false,
       hide_ccs_import_button: false,
       payment_enabled: false,
       table_default_page_size: 20,