📎 Add the blank line stylelint expects in the path bar styles

Stylelint (scss/double-slash-comment-empty-line-before) rejects the
comment right after a declaration, which made the frontend lint fail in
CI.

AI-assisted-by: claude-opus-5-5

frontend/src/app/main/ui/workspace/viewport/path_actions.scss

@@ -11,6 +11,7 @@
   cursor: initial;
   pointer-events: initial;
   position: absolute;
+
   // top and height stay physical: the transition below names them.
   top: var(--sp-xl);
   inset-inline-start: 50%;