feat(cms): CMS-driven homepages, products section, placeholder resolution

- Add ProductCard/ProductsSection schema and _products.html section macro
- Rewrite seed script with 3-platform homepage sections (wizard, OMS, loyalty),
  platform marketing pages, and store defaults with {{store_name}} placeholders
- Add resolve_placeholders() to ContentPageService for store default pages
- Fix SQLAlchemy filter bugs: replace Python `is None` with `.is_(None)` across
  all ContentPageService query methods (was silently breaking all platform page lookups)
- Remove hardcoded orion fallback and delete homepage-orion.html
- Add placeholder hint box with click-to-copy in admin content page editor
- Export ProductCard/ProductsSection from cms schemas __init__

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

app/modules/cms/schemas/homepage_sections.py

@@ -77,6 +77,25 @@ class FeatureCard(BaseModel):
     description: TranslatableText = Field(default_factory=TranslatableText)
 
 
+class ProductCard(BaseModel):
+    """Single product/offering card in products section."""
+
+    icon: str = ""
+    title: TranslatableText = Field(default_factory=TranslatableText)
+    description: TranslatableText = Field(default_factory=TranslatableText)
+    url: str = ""
+    badge: TranslatableText | None = None
+
+
+class ProductsSection(BaseModel):
+    """Product/offering showcase section (e.g. wizard.lu multi-product landing)."""
+
+    enabled: bool = True
+    title: TranslatableText = Field(default_factory=TranslatableText)
+    subtitle: TranslatableText | None = None
+    products: list[ProductCard] = Field(default_factory=list)
+
+
 class FeaturesSection(BaseModel):
     """Features section configuration."""
 
@@ -114,6 +133,7 @@ class HomepageSections(BaseModel):
     """Complete homepage sections structure."""
 
     hero: HeroSection | None = None
+    products: ProductsSection | None = None
     features: FeaturesSection | None = None
     pricing: PricingSection | None = None
     cta: CTASection | None = None
@@ -139,6 +159,10 @@ class HomepageSections(BaseModel):
                 subtitle=make_translatable(languages),
                 buttons=[],
             ),
+            products=ProductsSection(
+                title=make_translatable(languages),
+                products=[],
+            ),
             features=FeaturesSection(
                 title=make_translatable(languages),
                 features=[],
@@ -162,7 +186,7 @@ class HomepageSections(BaseModel):
 class SectionUpdateRequest(BaseModel):
     """Request to update a single section."""
 
-    section_name: str = Field(..., description="hero, features, pricing, or cta")
+    section_name: str = Field(..., description="hero, products, features, pricing, or cta")
     section_data: dict = Field(..., description="Section configuration")