fix: right-size warm tier for constrained platforms (#10746, #10705) (#10759)

* fix: right-size warm tier for constrained platforms and feed RP2040 watchdog during NodeDB save

* fix: size warm tier and traffic cache per-MCU RAM, lowering no-PSRAM ESP32 (classic/S2/C3) tiers

* docs: document nRF52/RP2040 #else fall-through in warm tier and TM cache cascades

src/mesh/NodeDB.cpp

@@ -66,6 +66,10 @@
 #include <utility/bonding.h>
 #endif
 
+#ifdef ARCH_RP2040
+#include <hardware/watchdog.h>
+#endif
+
 #if defined(ARCH_ESP32) && !MESHTASTIC_EXCLUDE_WIFI
 #include <MeshtasticOTA.h>
 #endif
@@ -2682,6 +2686,11 @@ bool NodeDB::saveNodeDatabaseToDisk()
     nodeDatabase.status.clear();
     nodeDatabase.status.shrink_to_fit();
 #if WARM_NODE_COUNT > 0
+#ifdef ARCH_RP2040
+    // nodes.proto + warm.dat are written back-to-back without the loop running between them;
+    // reset the 8s HW watchdog so the second write gets a full budget (issue #10746).
+    watchdog_update();
+#endif
     // Same cadence as the node DB; failure is logged but must not propagate —
     // a false return from here would trigger saveToDisk()'s fsFormat() path.
     warmStore.saveIfDirty();