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-cam-1.yaml

@@ -52,4 +52,4 @@ switch:
 #   - port: 8080
 #     mode: stream
 #   - port: 8081
-#     mode: snapshot
+#     mode: snapshot