feat: add vendor content pages management UI

- Add routes for vendor content pages list, create, and edit
- Create content-pages.html with tabs for Platform Defaults and My Pages
- Create content-page-edit.html for creating/editing pages
- Add JavaScript for both list and edit views
- Add "Content Pages" link to vendor sidebar under new "Shop" section
- Add show_in_legal field to vendor content pages API schemas
- Platform Defaults tab shows pages that can be overridden
- My Pages tab shows vendor's custom pages and overrides

Vendors can now:
- View platform default pages and override them with custom content
- Create entirely new custom pages for their shop
- Manage navigation placement (header, footer, legal)
- Publish/unpublish pages

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

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

app/routes/vendor_pages.py

@@ -527,6 +527,82 @@ async def vendor_billing_page(
     )
 
 
+# ============================================================================
+# CONTENT PAGES MANAGEMENT
+# ============================================================================
+
+
+@router.get(
+    "/{vendor_code}/content-pages", response_class=HTMLResponse, include_in_schema=False
+)
+async def vendor_content_pages_list(
+    request: Request,
+    vendor_code: str = Path(..., description="Vendor code"),
+    current_user: User = Depends(get_current_vendor_from_cookie_or_header),
+):
+    """
+    Render content pages management page.
+    Shows platform defaults (can be overridden) and vendor custom pages.
+    """
+    return templates.TemplateResponse(
+        "vendor/content-pages.html",
+        {
+            "request": request,
+            "user": current_user,
+            "vendor_code": vendor_code,
+        },
+    )
+
+
+@router.get(
+    "/{vendor_code}/content-pages/create",
+    response_class=HTMLResponse,
+    include_in_schema=False,
+)
+async def vendor_content_page_create(
+    request: Request,
+    vendor_code: str = Path(..., description="Vendor code"),
+    current_user: User = Depends(get_current_vendor_from_cookie_or_header),
+):
+    """
+    Render content page creation form.
+    """
+    return templates.TemplateResponse(
+        "vendor/content-page-edit.html",
+        {
+            "request": request,
+            "user": current_user,
+            "vendor_code": vendor_code,
+            "page_id": None,
+        },
+    )
+
+
+@router.get(
+    "/{vendor_code}/content-pages/{page_id}/edit",
+    response_class=HTMLResponse,
+    include_in_schema=False,
+)
+async def vendor_content_page_edit(
+    request: Request,
+    vendor_code: str = Path(..., description="Vendor code"),
+    page_id: int = Path(..., description="Content page ID"),
+    current_user: User = Depends(get_current_vendor_from_cookie_or_header),
+):
+    """
+    Render content page edit form.
+    """
+    return templates.TemplateResponse(
+        "vendor/content-page-edit.html",
+        {
+            "request": request,
+            "user": current_user,
+            "vendor_code": vendor_code,
+            "page_id": page_id,
+        },
+    )
+
+
 # ============================================================================
 # DYNAMIC CONTENT PAGES (CMS)
 # ============================================================================