Add automatic red and black night mode for color screens

Default to one hour after sunset through sunrise, using fresh cached GPS or recent direct RF neighbor locations. Provide saved CLI and WebConfig controls with a small integer solar approximation and no additional framebuffer.

.github/workflows/run-unit-tests.yml

@@ -1175,6 +1175,9 @@ jobs:
           python3 -B test/test_backlight_poll_rollover.py -v
           python3 -B test/test_rgb_led_rollover.py -v
           python3 -B test/test_display_power.py
+          python3 -B test/test_display_night_mode.py -v
+          python3 -B test/test_display_night_location.py -v
+          python3 -B test/test_display_night_rendering.py -v
           python3 -B test/test_t114_display_detection.py -v
           python3 -B test/test_rc32_display_detection.py -v
           python3 -B test/test_wireless_tracker_display_detection.py -v
@@ -1206,6 +1209,7 @@ jobs:
           python3 -B test/test_webconfig_ui_runtime.py
           python3 -B test/test_webconfig_lost_reply.py -v
           python3 -B test/test_webconfig_cpu_frequency.py -v
+          python3 -B test/test_display_night_webconfig.py -v
           MESHCORE_REQUIRE_ROOM_BROWSER=1 python3 -B test/test_room_web_ui.py -v
           MESHCORE_REQUIRE_ROOM_BROWSER=1 python3 -B test/test_room_mail_web_ui.py -v