feat: expand companion platform, device controls, and memoir workflows

Add customer and operator login, BLE provisioning, device fleet controls, call memory, memoir generation, and refreshed family and maintenance portals. Include API contracts, migrations, firmware sources, tests, assets, and deployment documentation.

firmware/echoear-platform-agent/main/device_control.h

@@ -0,0 +1,10 @@
+#pragma once
+#include "esp_err.h"
+#include <stdbool.h>
+// Starts after network and factory identity initialization. Uses a PSRAM stack.
+esp_err_t device_control_start(void);
+void device_control_heartbeat(void);
+// Call from an application task, never from the MQTT event handler.
+void device_control_prepare_restart(void);
+// The touch task queues a wake; the control worker restores power and syncs it.
+bool device_control_request_screen_wake(void);