feat: add vendor dropdown and show_in_legal to content page editor

- Load vendors dynamically in content page editor dropdown
- Add show_in_legal field to default content pages seed script
- Set privacy and terms pages to show_in_legal=true, show_in_footer=false
- Update page creation in seed script to use show_in_legal

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

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

static/admin/js/content-page-edit.js

@@ -31,7 +31,9 @@ function contentPageEditor(pageId) {
             display_order: 0,
             vendor_id: null
         },
+        vendors: [],
         loading: false,
+        loadingVendors: false,
         saving: false,
         error: null,
         successMessage: null,
@@ -48,6 +50,9 @@ function contentPageEditor(pageId) {
             }
             window._contentPageEditInitialized = true;
 
+            // Load vendors for dropdown
+            await this.loadVendors();
+
             if (this.pageId) {
                 // Edit mode - load existing page
                 contentPageEditLog.group('Loading page for editing');
@@ -61,6 +66,23 @@ function contentPageEditor(pageId) {
             contentPageEditLog.info('=== CONTENT PAGE EDITOR INITIALIZATION COMPLETE ===');
         },
 
+        // Load vendors for dropdown
+        async loadVendors() {
+            this.loadingVendors = true;
+            try {
+                contentPageEditLog.info('Loading vendors...');
+                const response = await apiClient.get('/admin/vendors?is_active=true&limit=100');
+                const data = response.data || response;
+                this.vendors = data.items || data || [];
+                contentPageEditLog.info(`Loaded ${this.vendors.length} vendors`);
+            } catch (err) {
+                contentPageEditLog.error('Error loading vendors:', err);
+                this.vendors = [];
+            } finally {
+                this.loadingVendors = false;
+            }
+        },
+
         // Load existing page
         async loadPage() {
             this.loading = true;