Fix trailing spaces and missing newlines in all mcu-*.yaml files

Bulk cleanup: remove trailing whitespace and ensure files end with a
newline. Structural issues (indentation, bracket spacing) left for
per-file fixes.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

mcu-lvgl-trainer.yaml

@@ -28,13 +28,13 @@ i2c:
 psram:
   mode: octal
   speed: 80MHz
-  
+
 spi:
   id: display_qspi
   type: quad
   clk_pin: 47
   data_pins: [21, 48, 40, 39]
-    
+
 color:
   - id: my_red
     red: 100%
@@ -140,7 +140,7 @@ touchscreen:
     display: main_display
     i2c_id: touchscreen_bus
     update_interval: 100ms
-    # interrupt_pin: 
+    # interrupt_pin:
       # number: 3
       # ignore_strapping_warning: true
     calibration:
@@ -286,4 +286,4 @@ lvgl:
             - homeassistant.action:
                 action: light.toggle
                 data:
-                    entity_id: light.mcu_dimmer_exercise_room_fan
+                    entity_id: light.mcu_dimmer_exercise_room_fan