words: active-block marker → the gutter (not the block) + no select in preview

Two fixes from feedback:

- The active/hovered-block marker belonged in the GUTTER, not as an overlay
  on the block. `[data-words-block-outline]` is now a thin (3px) vertical
  accent rail pinned to the gutter column (left margin, just left of where
  the text begins) spanning the block's height — only top/height track the
  block. Replaces the tinted fill that landed on the block content.
- Preview is read-only, but `WordsActivate` (click-to-select → the dotted
  active outline) still ran, so blocks could be selected in preview. Add an
  `enabled` prop (false in preview): no click-activation and the active stamp
  is cleared. `<Words>` passes `enabled={mode === 'edit'}`.

Verified in-browser: the gutter rail sits 8px left of the block text (not
over it), spanning the block height; clicking a block in preview no longer
stamps `data-words-active`. Check clean for the touched files.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/uix/eidos/components/words/words-activate.svelte

@@ -28,11 +28,15 @@
 	let {
 		api,
 		content,
-		dom
+		dom,
+		enabled = true
 	}: {
 		api: ProviderSnippetProps;
 		content: HTMLElement;
 		dom: ActiveDom;
+		/** When false (preview / read-only) block activation is off: no
+		 *  click-to-select and the active-block outline is cleared. */
+		enabled?: boolean;
 	} = $props();
 
 	// Build the MATERIALIZED-PATH id of the clicked block: walk the DOM up
@@ -52,7 +56,7 @@
 	}
 
 	$effect(() => {
-		if (!content) return;
+		if (!content || !enabled) return;
 		const onPointerDown = (e: Event) => {
 			const target = e.target as HTMLElement | null;
 			if (!target) return;
@@ -76,6 +80,7 @@
 	// are unique, so we match the LAST segment. The segment count is the
 	// nesting depth → `data-words-depth`.
 	$effect(() => {
+		const on = enabled; // re-run (and clear) when activation is turned off
 		const idPath = api.activeBlockId;
 		// Touch `html` so this effect re-runs after each re-render and
 		// re-stamps the (freshly recreated) element.
@@ -88,7 +93,8 @@
 			prev.removeAttribute('data-words-active');
 			prev.removeAttribute('data-words-depth');
 		}
-		if (!idPath) return;
+		// Preview / read-only: stamps cleared above, never re-applied.
+		if (!on || !idPath) return;
 		const segments = idPath.split('/').filter(Boolean);
 		const localId = segments[segments.length - 1];
 		if (!localId) return;

src/uix/eidos/components/words/words-block-gutter.svelte

@@ -314,11 +314,11 @@
 
 {#if (show || menuOpen) && rect}
 	{#if inGutter || menuOpen}
-		<div
-			data-words-block-outline
-			style="top: {rect.top - 3}px; left: {rect.left - 3}px; width: {rect.width +
-				6}px; height: {rect.height + 6}px;"
-		></div>
+		<!-- Active-block marker: a vertical accent BAR in the gutter (left
+		     margin), spanning the block's height. NOT an overlay on the block
+		     itself — the CSS pins it to the gutter column; only top/height
+		     track the block. -->
+		<div data-words-block-outline style="top: {rect.top}px; height: {rect.height}px;"></div>
 	{/if}
 	<!-- Center the handle vertically against the block's height: position
 	     it at the block midpoint and let `transform: translateY(-50%)`

src/uix/eidos/components/words/words.css

@@ -179,16 +179,17 @@
 	transform: translateX(1px) scale(1.18);
 }
 
-/* Active-block highlight while the handle acts on a block: a faint tinted
-   fill + a solid accent bar on the left edge (toward the gutter grip). Reads
-   as "this is the block" far better than the old dashed outline. */
+/* Active-block marker — a vertical accent rail in the GUTTER (left margin),
+   NOT on the block. Only top/height come from the block (set inline); the
+   bar is pinned to the gutter column, just inside where the text begins. */
 [data-words-block-outline] {
 	position: absolute;
+	inset-inline-start: calc(var(--_words-content-px) - 0.7rem);
 	z-index: 1;
+	inline-size: 3px;
+	border-radius: 2px;
+	background: color-mix(in srgb, var(--color-primary-solid) 55%, transparent);
 	pointer-events: none;
-	background: color-mix(in srgb, var(--color-primary-solid) 5%, transparent);
-	border-radius: var(--words-radius-sm);
-	box-shadow: inset 3px 0 0 color-mix(in srgb, var(--color-primary-solid) 40%, transparent);
 	animation: words-outline-in var(--words-transition-duration) var(--words-transition-ease);
 }
 @keyframes words-outline-in {

src/uix/eidos/components/words/words.svelte

@@ -109,7 +109,7 @@
 				<WordsBubble {api} />
 			{/if}
 			{#if contentEl}
-				<WordsActivate {api} content={contentEl} {dom} />
+				<WordsActivate {api} content={contentEl} {dom} enabled={mode === 'edit'} />
 				{#if mode === 'edit'}
 					<WordsBlockGutter {api} content={contentEl} {dom} />
 					<WordsBlockDrag {api} content={contentEl} {dom} />