feat: implement complete CMT backend with API endpoints and test suite

- Add 7 core API endpoints: users, transactions, partners, products, inventory, payments, credit
- Implement role-based authentication (admin/write/read-only access)
- Add comprehensive database models with proper relationships
- Include full test coverage for all endpoints and business logic
- Set up Alembic migrations and Docker configuration
- Configure FastAPI app with CORS and database integration

.vscode/settings.json

@@ -2,12 +2,21 @@
   "github.copilot.advanced": {
     "ignore": [
       "**/.env",
-      "**/.env.*",
+      "**/.env.*", 
+      "**/.env.local",
+      "**/.env.production",
+      "**/.env.development",
       "**/secrets/**",
       "**/*.key",
-      "**/*.pem"
+      "**/*.pem",
+      "**/.env.example",
+      "**/config/*.env"
     ]
   },
+  "github.copilot.enable": {
+    "plaintext": false,
+    "properties": false
+  },
   "sqltools.connections": [
     {
       "previewLimit": 50,