Add ability to turn off heartbeat LED blinking (#3674)

* Add ability to turn off status LED blinking

Fixes #3635 and depends on [protobufs PR #485](https://github.com/meshtastic/protobufs/pull/485)

Signed-off-by: Andrew Yong <me@ndoo.sg>

* led_heartbeat_disabled

* trunk

---------

Signed-off-by: Andrew Yong <me@ndoo.sg>
Co-authored-by: Ben Meadors <benmmeadors@gmail.com>

src/main.cpp

@@ -179,6 +179,11 @@ const char *getDeviceName()
 
 static int32_t ledBlinker()
 {
+    // Still set up the blinking (heartbeat) interval but skip code path below, so LED will blink if
+    // config.device.led_heartbeat_disabled is changed
+    if (config.device.led_heartbeat_disabled)
+        return 1000;
+
     static bool ledOn;
     ledOn ^= 1;
 
@@ -1001,4 +1006,4 @@ void loop()
         mainDelay.delay(delayMsec);
     }
     // if (didWake) LOG_DEBUG("wake!\n");
-}
+}