fix(scripts): fix model registration and missing platform_id in init scripts

All init scripts (init_log_settings, create_default_content_pages,
create_platform_pages, seed_email_templates) failed because they didn't
register all SQLAlchemy model classes, causing mapper resolution errors
for cross-module relationships (Platform→ContentPage, Platform→SubscriptionTier).

Fixes:
- Add full model registration loop to all 5 init scripts
- Add platform_id (OMS) to content page creation (NOT NULL constraint)
- Add missing db.commit() to create_platform_pages.py (pages were never persisted)
- Add cms.models to init_production.py registration list

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

scripts/create_default_content_pages.py

@@ -36,8 +36,27 @@ sys.path.insert(0, str(project_root))
 from sqlalchemy import select
 from sqlalchemy.orm import Session
 
+# Register all models with SQLAlchemy so string-based relationships resolve
+for _mod in [
+    "app.modules.billing.models",
+    "app.modules.inventory.models",
+    "app.modules.cart.models",
+    "app.modules.messaging.models",
+    "app.modules.loyalty.models",
+    "app.modules.catalog.models",
+    "app.modules.customers.models",
+    "app.modules.orders.models",
+    "app.modules.marketplace.models",
+    "app.modules.cms.models",
+]:
+    try:
+        __import__(_mod)
+    except ImportError:
+        pass
+
 from app.core.database import SessionLocal
 from app.modules.cms.models import ContentPage
+from app.modules.tenancy.models import Platform
 
 # ============================================================================
 # DEFAULT PAGE CONTENT
@@ -470,6 +489,15 @@ def create_default_pages(db: Session) -> None:
     print("Creating Default Platform Content Pages (CMS)")
     print("=" * 70 + "\n")
 
+    # Resolve OMS platform for platform_id
+    oms_platform = db.execute(
+        select(Platform).where(Platform.code == "oms")
+    ).scalar_one_or_none()
+    if not oms_platform:
+        print("  ⚠️  OMS platform not found. Run init_production.py first.")
+        return
+    platform_id = oms_platform.id
+
     created_count = 0
     skipped_count = 0
 
@@ -490,6 +518,7 @@ def create_default_pages(db: Session) -> None:
 
         # Create new platform default page
         page = ContentPage(
+            platform_id=platform_id,
             store_id=None,  # Platform default
             slug=page_data["slug"],
             title=page_data["title"],