fix(workbench): tighten SceneHeader spacing and keep contenteditable clean

Two small follow-ups to the inline-edit header:

- Reduce the right padding from 2.5rem to 0.25rem so the scene name
  sits visually adjacent to the first card. With the carousel's own
  1rem gap between flex children the total breathing room is now
  ~20px instead of ~56px, which matches how hero titles usually
  relate to the cards below / beside them.
- prettier-ignore on the <h1> and <p> element blocks. Prettier's
  default Svelte formatting moved {scene.name} onto its own line
  with indentation whitespace, which contenteditable renders
  verbatim as literal leading / trailing spaces in the editor
  content. Keep the mustache on the same line as the tag so the
  text value is what the store actually holds.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

apps/mana/apps/web/src/lib/components/workbench/scenes/SceneHeader.svelte

@@ -75,6 +75,7 @@
 
 {#if scene}
 	<div class="scene-header">
+		<!-- prettier-ignore -->
 		<!-- svelte-ignore a11y_no_noninteractive_element_to_interactive_role -->
 		<h1
 			class="scene-name"
@@ -89,6 +90,7 @@
 		>
 			{scene.name}
 		</h1>
+		<!-- prettier-ignore -->
 		<!-- svelte-ignore a11y_no_noninteractive_element_to_interactive_role -->
 		<p
 			class="scene-desc"
@@ -112,7 +114,7 @@
 	.scene-header {
 		width: 420px;
 		max-width: 60vw;
-		padding: 2rem 2.5rem 2rem 0;
+		padding: 2rem 0.25rem 2rem 0;
 		display: flex;
 		flex-direction: column;
 		gap: 0.75rem;
@@ -183,7 +185,7 @@
 	@media (max-width: 639px) {
 		.scene-header {
 			width: 280px;
-			padding: 1.25rem 1.5rem 1.25rem 0;
+			padding: 1.25rem 0.25rem 1.25rem 0;
 			gap: 0.5rem;
 		}
 		.scene-desc {