feat(studio): wrap gutter names instead of truncating them

A truncated name needs a hover to be read at all, and a tooltip is no use
for a name you are scanning a column of. All three gutter labels — the
plain track header, the group header, and the keyframe layer row — now
wrap and drop their `title`.

`break-words` so a long single token breaks rather than forcing the column
wider. Measured at the 232px gutter: a name long enough to wrap takes two
lines (28px) inside the 48px row with room to spare; a third line would
overflow, which is what the row affords either way.

One test located the name by its `title` and now reads the rendered text.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

packages/studio/src/player/components/LayerDisclosureRow.tsx

@@ -95,9 +95,9 @@ export function LayerDisclosureRow({
       <span aria-hidden="true" className="shrink-0 text-[13px] leading-none text-white/40">
         ◇
       </span>
-      <span className="min-w-0 flex-1 truncate font-medium" title={name}>
-        {name}
-      </span>
+      {/* Wraps rather than truncating: a truncated name needs a hover to be
+          read, which a scanned column cannot rely on. */}
+      <span className="min-w-0 flex-1 break-words font-medium leading-tight">{name}</span>
       <TrackClipCount clipCount={clipCount} />
       {children}
       {/* Anchored right, on every header that has one: the lane toggle is the

packages/studio/src/player/components/TimelineGroupHeader.tsx

@@ -65,7 +65,9 @@ function GroupNameButton({
       <span aria-hidden="true" className="shrink-0 text-[12px] leading-none text-white/50">
         ▤
       </span>
-      <span className="min-w-0 truncate font-medium">{label}</span>
+      {/* Wraps rather than truncating — a name that needs a hover to be read
+          is no use in a column you scan. */}
+      <span className="min-w-0 break-words text-left font-medium leading-tight">{label}</span>
       <span
         className="shrink-0 rounded-full bg-white/10 px-1 text-[9px] leading-[14px] tabular-nums text-white/55"
         aria-hidden="true"
@@ -107,7 +109,7 @@ export function TimelineGroupHeader({
       }}
     >
       {/* One line, like a track header's: caret and name, then every control
-          anchored to the right edge. The name truncates and the controls are
+          anchored to the right edge. The name wraps and the controls are
           `shrink-0`, so they hold the edge and the name gives way — no second
           line needed to keep five controls off the label. */}
       <button

packages/studio/src/player/components/TimelineTrackHeader.test.tsx

@@ -747,7 +747,9 @@ describe("TimelineTrackHeader", () => {
     it("names the header for the track, not for one of the clips on it", () => {
       const view = renderHeader({ ...ROW, keyframeClip: NARRATION_2 });
       expect(view.host.textContent).not.toContain("narration-2");
-      expect(view.host.querySelector('[title="Track 1"]')?.textContent).toBe("Track 1");
+      // Asserted on the rendered text, not a `title`: the name wraps now rather
+      // than truncating, so it no longer carries a tooltip to be found by.
+      expect(view.host.textContent).toContain("Track 1");
       // Alone on the track it is still named for itself.
       view.rerender({
         ...ROW,
@@ -755,7 +757,7 @@ describe("TimelineTrackHeader", () => {
         trackElements: [NARRATION_2],
         clipCount: 1,
       });
-      expect(view.host.querySelector('[title="narration-2"]')?.textContent).toBe("narration-2");
+      expect(view.host.textContent).toContain("narration-2");
       act(() => view.root.unmount());
     });
   });

packages/studio/src/player/components/TimelineTrackPlainHeader.tsx

@@ -89,14 +89,16 @@ export function PlainTrackHeader({
         {isAudioTrack && (
           <Music size={12} weight="fill" aria-hidden="true" className="text-white/35" />
         )}
-        {/* No `flex-1`: the name takes only the width it needs (still
-            truncating at `min-w-0` when the row is narrow) so the clip count
-            sits against it rather than being pushed out to meet the controls.
-            The slack goes to the `ml-auto` group below instead. */}
+        {/* No `flex-1`: the name takes only the width it needs, so the clip
+            count sits against it rather than being pushed out to meet the
+            controls. The slack goes to the `ml-auto` group below instead.
+
+            Wraps rather than truncating: a truncated name needs a hover to be
+            read at all, and a tooltip is no use to a name you are scanning a
+            column of. `break-words` so a long single token breaks instead of
+            forcing the column wider. */}
         {showTrackLabel && (
-          <span className="min-w-0 truncate text-[11px]" title={trackLabel}>
-            {trackLabel}
-          </span>
+          <span className="min-w-0 break-words text-[11px] leading-tight">{trackLabel}</span>
         )}
         {showTrackLabel && <TrackClipCount clipCount={clipCount} />}
         {/* `ml-auto` is what anchors the group right: it absorbs the slack the