Add heltec_v4 board. (#7845)

* add heltec_v4 board.

* Update variants/esp32s3/heltec_v4/platformio.ini

Co-authored-by: Austin <vidplace7@gmail.com>

* Limit the maximum output power.

* Trunk fixes

Fixes formatting to match meshtastic trunk linter.

* Apply suggestion from @Copilot

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

* Apply suggestion from @Copilot

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

---------

Co-authored-by: Ben Meadors <benmmeadors@gmail.com>
Co-authored-by: Austin <vidplace7@gmail.com>
Co-authored-by: Tom Fifield <tom@tomfifield.net>
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

variants/esp32s3/heltec_v4/platformio.ini

@@ -0,0 +1,10 @@
+[env:heltec-v4] 
+extends = esp32s3_base
+board = heltec_v4
+board_check = true
+build_flags = 
+  ${esp32s3_base.build_flags}
+  -D HELTEC_V4
+  -I variants/esp32s3/heltec_v4
+  -D GPS_POWER_TOGGLE ; comment this line to disable triple press function on the user button to turn off gps entirely.
+  -D SX126X_MAX_POWER=11