Fix customer list display and make database fields optional

app/models.py

@@ -23,12 +23,12 @@ class Customer(Base):
     created_at = Column(DateTime, default=datetime.utcnow)
     updated_at = Column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)
     
-    # Database credentials
-    db_host = Column(String(100), nullable=False)
-    db_port = Column(Integer, nullable=False, default=3306)  # Default MySQL port
-    db_user = Column(String(100), nullable=False)
-    db_password = Column(String(100), nullable=False)
-    db_name = Column(String(100), nullable=False)
+    # Database credentials (optional for API-based architecture)
+    db_host = Column(String(100), nullable=True)
+    db_port = Column(Integer, nullable=True, default=3306)  # Default MySQL port
+    db_user = Column(String(100), nullable=True)
+    db_password = Column(String(100), nullable=True)
+    db_name = Column(String(100), nullable=True)
 
     # Relationship with call records
     call_records = relationship("CallRecord", back_populates="customer", cascade="all, delete-orphan")

app/static/admin.html

@@ -392,7 +392,7 @@
             loading.style.display = 'block';
 
             try {
-                const response = await fetch('/api/v1/customers', {
+                const response = await fetch('/api/v1/customers/', {
                     headers: {
                         'Authorization': `Bearer ${accessToken}`
                     }