flash cleaning improvements

zephcore/app/main_observer.cpp

@@ -32,6 +32,7 @@
 LOG_MODULE_REGISTER(zephcore_observer_main, CONFIG_ZEPHCORE_MAIN_LOG_LEVEL);
 
 #include <app/RepeaterDataStore.h>
+#include "../adapters/datastore/ZephyrFsFormat.h"
 #include <app/ObserverMesh.h>
 #include <adapters/clock/ZephyrRTCClock.h>
 #include <mesh/RadioIncludes.h>
@@ -306,6 +307,24 @@ int main(void)
 	}
 #endif
 
+	/* First boot on a volume that is not this role's - a fresh chip, a
+	 * companion, or a node that was running Arduino MeshCore, whose nRF52
+	 * filesystems overlap our lfs_partition
+	 * (devdocs/HANDOVER_lfs_arduino_overlap.md).  Erase everything so we
+	 * start from a known state: Zephyr's automount only
+	 * auto-formats the LittleFS volume when it fails to mount, and never
+	 * touches storage_partition (BLE bonds NVS) or QSPI.
+	 *
+	 * Self-limiting, so it needs no "done" marker: the identity is generated
+	 * and saved a few lines below, and loadPrefs() persists defaults on the
+	 * same boot, so the next boot sees this role's data and skips this. */
+	if (!data_store.hasRoleData()) {
+		LOG_WRN("Volume holds no data for this role - formatting before first boot");
+		if (!zephcore_fs_format_all(nullptr)) {
+			LOG_ERR("First-boot format failed - /lfs is not mounted");
+		}
+	}
+
 	/* Initialize LittleFS data store */
 	if (!data_store.begin()) {
 		LOG_ERR("RepeaterDataStore init failed");