For our first position send on boot, validate that we have received a fresh position (#9023)

src/mesh/NodeDB.h

@@ -279,9 +279,13 @@ class NodeDB
         LOG_DEBUG("Set local position: lat=%i lon=%i time=%u timestamp=%u", position.latitude_i, position.longitude_i,
                   position.time, position.timestamp);
         localPosition = position;
+        if (position.latitude_i != 0 || position.longitude_i != 0) {
+            localPositionUpdatedSinceBoot = true;
+        }
     }
 
     bool hasValidPosition(const meshtastic_NodeInfoLite *n);
+    bool hasLocalPositionSinceBoot() const { return localPositionUpdatedSinceBoot; }
 
 #if !defined(MESHTASTIC_EXCLUDE_PKI)
     bool checkLowEntropyPublicKey(const meshtastic_Config_SecurityConfig_public_key_t &keyToTest);
@@ -301,6 +305,7 @@ class NodeDB
 
   private:
     bool duplicateWarned = false;
+    bool localPositionUpdatedSinceBoot = false;
     uint32_t lastNodeDbSave = 0;    // when we last saved our db to flash
     uint32_t lastBackupAttempt = 0; // when we last tried a backup automatically or manually
     uint32_t lastSort = 0;          // When last sorted the nodeDB