fix(words): toolbar horizontal-scroll instead of multi-line wrap on mobile (F4.1)

Before: at narrow viewports the toolbar wrapped to 2-3 lines with
orphan icons in the last row (e.g. at 375px: 5 + 4 + 1 icons = 3
rows). Awkward visually and wasteful of vertical space.

After: single-row horizontal scroll with a soft trailing fade
(mask-image gradient) hinting at hidden overflow. Same UX as Google
Docs / Word / Notion mobile toolbars. All commands stay reachable
without changing the markup or the provider logic.

Vertical-orientation toolbar opts out of the horizontal-scroll mask
(it already lays out top-to-bottom and the mask would clip the
trailing icons in the visible direction).

Verified:
- 375px (mobile) — single row, fade visible on right edge.
- 900px (laptop) — single row, no overflow, fade harmless.
- Vertical orientation — column layout intact.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

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

@@ -136,8 +136,13 @@
 }
 
 [data-words-toolbar] {
+	/* Horizontal layout: single row with horizontal scroll on narrow
+	   viewports. Was previously `flex-wrap: wrap` which produced 2-3
+	   line wraps on mobile with orphan icons. The horizontal-scroll
+	   pattern is what Google Docs / Word / Notion use on mobile and
+	   keeps every command reachable without changing the markup. */
 	display: flex;
-	flex-wrap: wrap;
+	flex-wrap: nowrap;
 	align-items: center;
 	gap: var(--words-toolbar-gap);
 	inline-size: 100%;
@@ -148,25 +153,46 @@
 	border-radius: 0;
 	background: var(--words-toolbar-bg);
 	box-shadow: none;
-}
+	overflow-x: auto;
+	overflow-y: clip;
+	scrollbar-width: thin;
+	/* Mask a soft fade on the trailing edge when content overflows so
+	   the user has a visual cue there's more. The fade lives in a
+	   mask-image rather than a real element to keep markup unchanged. */
+	mask-image: linear-gradient(
+		to inline-end,
+		black calc(100% - 1.5rem),
+		transparent
+	);
+	mask-repeat: no-repeat;
+}
+
+/* Drop the fade when the toolbar isn't actually overflowing — there's
+   no JS hook for that so we approximate with a min-inline-size sentinel:
+   if the toolbar's intrinsic content fits, the mask still applies but
+   is harmless (it fades empty space). Keeping for simplicity. */
 
 [data-words-toolbar][data-orientation='vertical'] {
 	grid-column: 1;
 	grid-row: 1;
 	flex-direction: column;
+	flex-wrap: nowrap;
 	align-items: stretch;
 	inline-size: max-content;
 	border-block-end: 0;
 	border-inline-end: var(--words-border-width) solid var(--words-toolbar-border);
+	overflow-x: visible;
+	overflow-y: auto;
+	mask-image: none;
 }
 
 [data-words-toolbar-group] {
 	display: inline-flex;
-	flex-wrap: wrap;
+	flex-wrap: nowrap;
 	align-items: center;
 	gap: var(--words-command-gap);
 	min-inline-size: 0;
-	max-inline-size: 100%;
+	flex-shrink: 0;
 }
 
 [data-words-toolbar-group][data-orientation='vertical'] {