docs: [#220] update architecture docs for running services validator

- Added running_services.rs to remote actions validators list
- Documented that it validates all configured HTTP tracker instances
- Clarifies validator is correctly placed in infrastructure layer

Author: josecelano

docs/codebase-architecture.md

@@ -349,6 +349,7 @@ Application-specific template rendering and configuration for external tools:
 - ✅ `src/infrastructure/remote_actions/validators/cloud_init.rs` - Validate cloud-init completion
 - ✅ `src/infrastructure/remote_actions/validators/docker.rs` - Verify Docker installation
 - ✅ `src/infrastructure/remote_actions/validators/docker_compose.rs` - Validate Docker Compose
+- ✅ `src/infrastructure/remote_actions/validators/running_services.rs` - Validate tracker services (validates all HTTP tracker instances)
 
 **Persistence Layer:**