test(web/tuning): marker summary appears in tooltips too — use getAllByText

The knob-turn summary renders both as the sparkline tick tooltips (one
per series) and in the list under the chart; the single-element query
tripped on the duplicates in CI run 1906.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01TsF3cNoKrqCYsU78cXC8U6

web/src/routes/admin/tuning/tuning.test.ts

@@ -178,8 +178,11 @@ describe('Admin tuning page', () => {
     // Latest skip rate column for radio = 40% (also discover's latest
     // completion, hence getAllBy).
     expect(screen.getAllByText('40%').length).toBeGreaterThan(0);
-    // The knob turn is listed under the chart.
-    expect(screen.getByText(/2026-06-30 — radio: taste_weight 1→2/)).toBeInTheDocument();
+    // The knob turn is listed under the chart AND tooltipped on each
+    // sparkline's marker tick, hence getAllBy.
+    expect(
+      screen.getAllByText(/2026-06-30 — radio: taste_weight 1→2/).length
+    ).toBeGreaterThan(0);
     // Low-volume series (5 plays) is dimmed as anecdote.
     expect(screen.getByTitle(/fewer than 20 plays in the window/i)).toBeInTheDocument();
   });