fix(cms): filter pricing tiers by platform_id on homepage

_get_tiers_data() was querying all active tiers across all platforms.
Now accepts platform_id parameter to scope tiers to the current platform.

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

app/modules/cms/routes/pages/platform.py

@@ -28,16 +28,20 @@ ROUTE_CONFIG = {
 }
 
 
-def _get_tiers_data(db: Session) -> list[dict]:
+def _get_tiers_data(db: Session, platform_id: int | None = None) -> list[dict]:
     """Build tier data for display in templates from database."""
     from app.modules.billing.models import SubscriptionTier, TierCode
 
+    filters = [
+        SubscriptionTier.is_active.is_(True),
+        SubscriptionTier.is_public.is_(True),
+    ]
+    if platform_id is not None:
+        filters.append(SubscriptionTier.platform_id == platform_id)
+
     tiers_db = (
         db.query(SubscriptionTier)
-        .filter(
-            SubscriptionTier.is_active == True,
-            SubscriptionTier.is_public == True,
-        )
+        .filter(*filters)
         .order_by(SubscriptionTier.display_order)
         .all()
     )
@@ -156,7 +160,7 @@ async def homepage(
         # Use CMS-based homepage with template selection
         context = get_platform_context(request, db)
         context["page"] = cms_homepage
-        context["tiers"] = _get_tiers_data(db)
+        context["tiers"] = _get_tiers_data(db, platform_id=platform_id)
 
         template_name = cms_homepage.template or "default"
         template_path = f"cms/platform/homepage-{template_name}.html"
@@ -167,7 +171,7 @@ async def homepage(
     # Fallback: Default homepage template with placeholder content
     logger.info("[HOMEPAGE] No CMS homepage found, using default template with placeholders")
     context = get_platform_context(request, db)
-    context["tiers"] = _get_tiers_data(db)
+    context["tiers"] = _get_tiers_data(db, platform_id=platform_id)
 
     return templates.TemplateResponse(
         "cms/platform/homepage-default.html",