DS4 merge: update QA.20 color lock to the rebuilt STREAKS billboard structure

Semantics preserved (step-up amber / step-down green); DS4 moved the
coloring into a sev object, so the source-lock regex is updated to match.

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

tests/unit/vyndrParityQA.test.js

@@ -112,8 +112,12 @@ describe('QA.20 — movement + status color semantics (Phase 2.5 surfaces)', ()
     expect(read('app/ledger/page.tsx')).toContain("textDecoration: 'line-through'");
   });
   it('lens difficulty: tougher = amber, softer = green — never inverted', () => {
+    // DS4 rebuilt the STREAKS billboard: difficulty coloring moved into a `sev`
+    // object, but the semantics are locked here — step-up must be amber, step-
+    // down must be green, and the two must not be swapped.
     const panel = read('components/StreaksPanel.tsx');
-    expect(panel).toMatch(/step up' \? 'var\(--amber[^']*' : [^:]*step down' \? 'var\(--g-a/);
+    expect(panel).toMatch(/step up'\s*\?\s*\{ color: 'var\(--amber/);
+    expect(panel).toMatch(/step down'\s*\?\s*\{ color: 'var\(--g-a/);
   });
 });