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-socket-02.yaml

@@ -74,7 +74,7 @@ output:
     pin: GPIO02
     id: led_blue
     inverted: True
-    
+
 sensor:
   - platform: hlw8012
     sel_pin: