feat: multi-module improvements across merchant, store, i18n, and customer systems

- Fix platform-grouped merchant sidebar menu with core items at root level
- Add merchant store management (detail page, create store, team page)
- Fix store settings 500 error by removing dead stripe/API tab
- Move onboarding translations to module-owned locale files
- Fix onboarding banner i18n with server-side rendering + context inheritance
- Refactor login language selectors to use languageSelector() function (LANG-002)
- Move HTTPException handling to global exception handler in merchant routes (API-003)
- Add language selector to all login pages and portal headers
- Fix customer module: drop order stats from customer model, add to orders module
- Fix admin menu config visibility for super admin platform context
- Fix storefront auth and layout issues
- Add missing i18n translations for onboarding steps (en/fr/de/lb)

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

app/modules/orders/migrations/versions/orders_002_customer_order_stats.py

@@ -0,0 +1,35 @@
+"""orders 002 - customer order stats table
+
+Revision ID: orders_002
+Revises: orders_001
+Create Date: 2026-03-07
+"""
+import sqlalchemy as sa
+
+from alembic import op
+
+revision = "orders_002"
+down_revision = "orders_001"
+branch_labels = None
+depends_on = None
+
+
+def upgrade() -> None:
+    op.create_table(
+        "customer_order_stats",
+        sa.Column("id", sa.Integer(), primary_key=True, index=True),
+        sa.Column("store_id", sa.Integer(), sa.ForeignKey("stores.id"), nullable=False, index=True),
+        sa.Column("customer_id", sa.Integer(), sa.ForeignKey("customers.id"), nullable=False, index=True),
+        sa.Column("total_orders", sa.Integer(), nullable=False, server_default="0"),
+        sa.Column("total_spent_cents", sa.Integer(), nullable=False, server_default="0"),
+        sa.Column("last_order_date", sa.DateTime(timezone=True), nullable=True),
+        sa.Column("first_order_date", sa.DateTime(timezone=True), nullable=True),
+        sa.Column("created_at", sa.DateTime(), server_default=sa.func.now(), nullable=False),
+        sa.Column("updated_at", sa.DateTime(), server_default=sa.func.now(), nullable=False),
+        sa.UniqueConstraint("store_id", "customer_id", name="uq_customer_order_stats_store_customer"),
+    )
+    op.create_index("idx_customer_order_stats_customer", "customer_order_stats", ["customer_id"])
+
+
+def downgrade() -> None:
+    op.drop_table("customer_order_stats")

app/modules/orders/models/__init__.py

@@ -5,6 +5,7 @@ Orders module database models.
 This module contains the canonical implementations of order-related models.
 """
 
+from app.modules.orders.models.customer_order_stats import CustomerOrderStats
 from app.modules.orders.models.invoice import (
     Invoice,
     InvoiceStatus,
@@ -15,6 +16,7 @@ from app.modules.orders.models.order import Order, OrderItem
 from app.modules.orders.models.order_item_exception import OrderItemException
 
 __all__ = [
+    "CustomerOrderStats",
     "Order",
     "OrderItem",
     "OrderItemException",

app/modules/orders/models/customer_order_stats.py

@@ -0,0 +1,52 @@
+# app/modules/orders/models/customer_order_stats.py
+"""
+Customer order statistics model.
+
+Tracks per-customer order aggregates (total orders, total spent, etc.)
+owned by the orders module. This separates order stats from the
+customer profile data owned by the customers module.
+"""
+
+from sqlalchemy import Column, DateTime, ForeignKey, Index, Integer, UniqueConstraint
+from sqlalchemy.orm import relationship
+
+from app.core.database import Base
+from models.database.base import TimestampMixin
+
+
+class CustomerOrderStats(Base, TimestampMixin):
+    """Aggregated order statistics per customer per store."""
+
+    __tablename__ = "customer_order_stats"
+
+    id = Column(Integer, primary_key=True, index=True)
+    store_id = Column(
+        Integer, ForeignKey("stores.id"), nullable=False, index=True
+    )
+    customer_id = Column(
+        Integer, ForeignKey("customers.id"), nullable=False, index=True
+    )
+    total_orders = Column(Integer, nullable=False, default=0)
+    total_spent_cents = Column(Integer, nullable=False, default=0)
+    last_order_date = Column(DateTime(timezone=True), nullable=True)
+    first_order_date = Column(DateTime(timezone=True), nullable=True)
+
+    # Relationships
+    store = relationship("Store")
+    customer = relationship("Customer")
+
+    __table_args__ = (
+        UniqueConstraint(
+            "store_id", "customer_id", name="uq_customer_order_stats_store_customer"
+        ),
+        Index("idx_customer_order_stats_customer", "customer_id"),
+    )
+
+    def __repr__(self):
+        return (
+            f"<CustomerOrderStats("
+            f"store_id={self.store_id}, "
+            f"customer_id={self.customer_id}, "
+            f"total_orders={self.total_orders}, "
+            f"total_spent_cents={self.total_spent_cents})>"
+        )

app/modules/orders/services/customer_order_service.py

@@ -13,10 +13,11 @@ Similar to how:
 """
 
 import logging
+from datetime import UTC, datetime
 
 from sqlalchemy.orm import Session
 
-from app.modules.orders.models import Order
+from app.modules.orders.models import CustomerOrderStats, Order
 
 logger = logging.getLogger(__name__)
 
@@ -89,6 +90,51 @@ class CustomerOrderService:
             .all()
         )
 
+    def record_order(
+        self,
+        db: Session,
+        store_id: int,
+        customer_id: int,
+        total_amount_cents: int,
+    ) -> CustomerOrderStats:
+        """
+        Record an order in customer order stats (upsert).
+
+        Args:
+            db: Database session
+            store_id: Store ID
+            customer_id: Customer ID
+            total_amount_cents: Order total in cents
+
+        Returns:
+            Updated CustomerOrderStats
+        """
+        stats = (
+            db.query(CustomerOrderStats)
+            .filter(
+                CustomerOrderStats.store_id == store_id,
+                CustomerOrderStats.customer_id == customer_id,
+            )
+            .first()
+        )
+        now = datetime.now(UTC)
+        if stats:
+            stats.total_orders = (stats.total_orders or 0) + 1
+            stats.total_spent_cents = (stats.total_spent_cents or 0) + total_amount_cents
+            stats.last_order_date = now
+        else:
+            stats = CustomerOrderStats(
+                store_id=store_id,
+                customer_id=customer_id,
+                total_orders=1,
+                total_spent_cents=total_amount_cents,
+                first_order_date=now,
+                last_order_date=now,
+            )
+            db.add(stats)
+        db.flush()
+        return stats
+
     def get_order_count(
         self,
         db: Session,

app/modules/orders/tests/unit/test_customer_order_stats.py

@@ -0,0 +1,84 @@
+# tests/unit/models/test_customer_order_stats.py
+"""Unit tests for CustomerOrderStats model."""
+
+import pytest
+from sqlalchemy.exc import IntegrityError
+
+from app.modules.orders.models.customer_order_stats import CustomerOrderStats
+
+
+@pytest.mark.unit
+@pytest.mark.database
+class TestCustomerOrderStatsModel:
+    """Test CustomerOrderStats model."""
+
+    def test_create_stats(self, db, test_store, test_customer):
+        """Test creating customer order stats."""
+        stats = CustomerOrderStats(
+            store_id=test_store.id,
+            customer_id=test_customer.id,
+            total_orders=3,
+            total_spent_cents=15000,
+        )
+        db.add(stats)
+        db.commit()
+        db.refresh(stats)
+
+        assert stats.id is not None
+        assert stats.store_id == test_store.id
+        assert stats.customer_id == test_customer.id
+        assert stats.total_orders == 3
+        assert stats.total_spent_cents == 15000
+
+    def test_default_values(self, db, test_store, test_customer):
+        """Test default values for stats."""
+        stats = CustomerOrderStats(
+            store_id=test_store.id,
+            customer_id=test_customer.id,
+        )
+        db.add(stats)
+        db.commit()
+        db.refresh(stats)
+
+        assert stats.total_orders == 0
+        assert stats.total_spent_cents == 0
+        assert stats.last_order_date is None
+        assert stats.first_order_date is None
+
+    def test_unique_constraint(self, db, test_store, test_customer):
+        """Test unique constraint on store_id + customer_id."""
+        stats1 = CustomerOrderStats(
+            store_id=test_store.id,
+            customer_id=test_customer.id,
+            total_orders=1,
+        )
+        db.add(stats1)
+        db.commit()
+
+        stats2 = CustomerOrderStats(
+            store_id=test_store.id,
+            customer_id=test_customer.id,
+            total_orders=2,
+        )
+        db.add(stats2)
+        with pytest.raises(IntegrityError):
+            db.commit()
+
+    def test_update_stats(self, db, test_store, test_customer):
+        """Test updating existing stats."""
+        stats = CustomerOrderStats(
+            store_id=test_store.id,
+            customer_id=test_customer.id,
+            total_orders=1,
+            total_spent_cents=5000,
+        )
+        db.add(stats)
+        db.commit()
+
+        stats.total_orders = 2
+        stats.total_spent_cents = 12000
+        db.commit()
+        db.refresh(stats)
+
+        assert stats.total_orders == 2
+        assert stats.total_spent_cents == 12000