Remove spi config as it's default now from qmk main and move backlight config to halcyon.c as we always want that to happen (display on slave otherwise wouldn't turn off)

users/halcyon_modules/halcyon.c

@@ -43,6 +43,20 @@ module_t module;
     module_t module = hlc_tft_display;
 #endif
 
+bool backlight_off = false;
+
+// Timeout handling
+void backlight_wakeup(void) {
+    backlight_off = false;
+    backlight_enable();
+}
+
+// Timeout handling
+void backlight_suspend(void) {
+    backlight_off = true;
+    backlight_disable();
+}
+
 void module_sync_slave_handler(uint8_t initiator2target_buffer_size, const void* initiator2target_buffer, uint8_t target2initiator_buffer_size, void* target2initiator_buffer) {
     if (initiator2target_buffer_size == sizeof(module)) {
         memcpy(&module_master, initiator2target_buffer, sizeof(module_master));
@@ -76,6 +90,15 @@ void housekeeping_task_kb(void) {
             display_module_housekeeping_task_kb(false); // Otherwise be the main display
         }
     }
+    
+    // Backlight feature
+    if (backlight_off && last_input_activity_elapsed() <= HLC_BACKLIGHT_TIMEOUT) {
+        backlight_wakeup();
+    }
+    if (!backlight_off && last_input_activity_elapsed() > HLC_BACKLIGHT_TIMEOUT) {
+        backlight_suspend();
+    }
+
     module_housekeeping_task_kb();
 
     housekeeping_task_user();