fix: add missing Subscription model class - maps to subscriptions table for customer service subscriptions

src/app/models/subscription.py

@@ -0,0 +1,83 @@
+"""
+Subscription Model - Customer service subscriptions
+Maps to 'subscriptions' table in docs/schema/schema.sql
+"""
+from sqlalchemy import Column, String, Text, Date, Numeric, ForeignKey, CheckConstraint
+from sqlalchemy.dialects.postgresql import UUID, JSONB
+from sqlalchemy.orm import relationship
+from app.models.base import BaseModel
+from app.models.enums import ServiceType, SubscriptionStatus, PayoutMethod
+
+
+class Subscription(BaseModel):
+    """
+    Subscription model - Tracks customer service subscriptions
+    Maps to 'subscriptions' table in docs/schema/schema.sql
+    
+    Purpose: Represent active/inactive customer service subscriptions
+    Links to customers, sales orders, and projects
+    """
+    __tablename__ = "subscriptions"
+    
+    # Relationships
+    customer_id = Column(UUID(as_uuid=True), ForeignKey('customers.id', ondelete='RESTRICT'), nullable=False)
+    sales_order_id = Column(UUID(as_uuid=True), ForeignKey('sales_orders.id', ondelete='SET NULL'), nullable=True)
+    project_id = Column(UUID(as_uuid=True), ForeignKey('projects.id', ondelete='RESTRICT'), nullable=True)
+    
+    # Service Details
+    service_type = Column(String(50), nullable=False)  # ServiceType enum
+    package_name = Column(Text, nullable=True)
+    monthly_fee = Column(Numeric(precision=12, scale=2), nullable=True)
+    
+    # Service Address (where service is active)
+    project_region_id = Column(UUID(as_uuid=True), ForeignKey('project_regions.id', ondelete='SET NULL'), nullable=True)
+    service_address_line1 = Column(Text, nullable=True)
+    service_address_line2 = Column(Text, nullable=True)
+    service_maps_link = Column(Text, nullable=True)
+    service_latitude = Column(Numeric(precision=10, scale=7), nullable=True)
+    service_longitude = Column(Numeric(precision=10, scale=7), nullable=True)
+    
+    # Equipment & Activation Details (Flexible JSONB storage)
+    equipment_details = Column(JSONB, default={}, nullable=False)
+    activation_details = Column(JSONB, default={}, nullable=False)
+    
+    # Payment Method
+    payment_method = Column(String(50), nullable=True)  # PayoutMethod enum
+    mobile_money_provider = Column(Text, nullable=True)
+    payment_phone = Column(Text, nullable=True)
+    payment_account_number = Column(Text, nullable=True)
+    payment_account_name = Column(Text, nullable=True)
+    
+    # Lifecycle
+    status = Column(String(50), default='pending_activation', nullable=False)  # SubscriptionStatus enum
+    activation_date = Column(Date, nullable=True)
+    cancellation_date = Column(Date, nullable=True)
+    suspension_date = Column(Date, nullable=True)
+    termination_date = Column(Date, nullable=True)
+    
+    # Metadata
+    notes = Column(Text, nullable=True)
+    additional_metadata = Column(JSONB, default={}, nullable=False)
+    activated_by_user_id = Column(UUID(as_uuid=True), ForeignKey('users.id', ondelete='SET NULL'), nullable=True)
+    
+    # Relationships
+    customer = relationship("Customer", back_populates="subscriptions")
+    sales_order = relationship("SalesOrder", foreign_keys=[sales_order_id])
+    project = relationship("Project", foreign_keys=[project_id])
+    project_region = relationship("ProjectRegion", foreign_keys=[project_region_id])
+    activated_by_user = relationship("User", foreign_keys=[activated_by_user_id])
+    
+    # Table constraints
+    __table_args__ = (
+        CheckConstraint(
+            'monthly_fee IS NULL OR monthly_fee >= 0',
+            name='chk_positive_fee'
+        ),
+        CheckConstraint(
+            'cancellation_date IS NULL OR activation_date IS NULL OR cancellation_date >= activation_date',
+            name='chk_cancellation_after_activation'
+        ),
+    )
+    
+    def __repr__(self):
+        return f"<Subscription(id='{self.id}', customer_id='{self.customer_id}', status='{self.status}')>"