feat(storefront): homepage, module gating, widget protocol, i18n fixes

Storefront homepage & module gating:
- CMS owns storefront GET / (slug="home" with 3-tier resolution)
- Catalog loses GET / (keeps /products only)
- Store root redirect (GET / → /store/dashboard or /store/login)
- Route gating: non-core modules return 404 when disabled for platform
- Seed store default homepages per platform

Widget protocol for customer dashboard:
- StorefrontDashboardCard contract in widgets.py
- Widget aggregator get_storefront_dashboard_cards()
- Orders and Loyalty module widget providers
- Dashboard template renders contributed cards (no module names)

Landing template module-agnostic:
- CTAs driven by storefront_nav (not hardcoded module names)
- Header actions check nav item IDs (not enabled_modules)
- Remove hardcoded "Add Product" sidebar button
- Remove all enabled_modules checks from storefront templates

i18n fixes:
- Title placeholder resolution ({{store_name}}) for store default pages
- Storefront nav label_keys prefixed with module code
- Add storefront.account.* keys to 6 modules (en/fr/de/lb)
- Header/footer CMS pages use get_translated_title(current_language)
- Footer labels use i18n keys instead of hardcoded English

Icon cleanup:
- Standardize on map-pin (remove location-marker alias)
- Replace all location-marker references across templates and docs

Docs:
- Storefront builder vision proposal (6 phases)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

app/modules/contracts/widgets.py

@@ -80,6 +80,44 @@ class WidgetContext:
     include_details: bool = False
 
 
+# =============================================================================
+# Storefront Dashboard Card
+# =============================================================================
+
+
+@dataclass
+class StorefrontDashboardCard:
+    """
+    A card contributed by a module to the storefront customer dashboard.
+
+    Modules implement get_storefront_dashboard_cards() to provide these.
+    The dashboard template renders them without knowing which module provided them.
+
+    Attributes:
+        key: Unique identifier (e.g. "orders.summary", "loyalty.points")
+        icon: Lucide icon name (e.g. "shopping-bag", "gift")
+        title: Card title (i18n key or plain text)
+        subtitle: Card subtitle / description
+        route: Link destination relative to base_url (e.g. "account/orders")
+        value: Primary display value (e.g. order count, points balance)
+        value_label: Label for the value (e.g. "Total Orders", "Points Balance")
+        order: Sort order (lower = shown first)
+        template: Optional custom template path for complex rendering
+        extra_data: Additional data for custom template rendering
+    """
+
+    key: str
+    icon: str
+    title: str
+    subtitle: str
+    route: str
+    value: str | int | None = None
+    value_label: str | None = None
+    order: int = 100
+    template: str | None = None
+    extra_data: dict[str, Any] = field(default_factory=dict)
+
+
 # =============================================================================
 # Widget Item Types
 # =============================================================================
@@ -330,6 +368,30 @@ class DashboardWidgetProviderProtocol(Protocol):
         """
         ...
 
+    def get_storefront_dashboard_cards(
+        self,
+        db: "Session",
+        store_id: int,
+        customer_id: int,
+        context: WidgetContext | None = None,
+    ) -> list["StorefrontDashboardCard"]:
+        """
+        Get cards for the storefront customer dashboard.
+
+        Called by the customer account dashboard. Each module contributes
+        its own cards (e.g. orders summary, loyalty points).
+
+        Args:
+            db: Database session for queries
+            store_id: ID of the store
+            customer_id: ID of the logged-in customer
+            context: Optional filtering/scoping context
+
+        Returns:
+            List of StorefrontDashboardCard objects
+        """
+        ...
+
 
 __all__ = [
     # Context
@@ -343,6 +405,8 @@ __all__ = [
     "WidgetData",
     # Main envelope
     "DashboardWidget",
+    # Storefront
+    "StorefrontDashboardCard",
     # Protocol
     "DashboardWidgetProviderProtocol",
 ]