Generator: context-aware variable refs — 444/831 (53%, +20)

Fixed ref() to map upstream JS variable names to let-bound SX variables
using element context (tag→var, id→var, make-return→last-var). Fixes
if (0→14/19), put (14→18), on (20→23), and other categories where the
upstream test uses make() return variables like d1, div, btn.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

tests/playwright/hs-behavioral.spec.js

@@ -256,6 +256,17 @@ test.describe('Hyperscript behavioral tests', () => {
     for (const [t, n] of Object.entries(errTypes).sort((a,b) => b[1] - a[1])) {
       console.log(`    ${t}: ${n}`);
     }
+    // Show sample failures per type
+    for (const [t, n] of Object.entries(errTypes).sort((a,b) => b[1] - a[1])) {
+      const samples = results.filter(r => !r.p).filter(r => {
+        const e = r.e || '';
+        if (t === 'crash') return e.includes('callFn');
+        if (t === 'stub') return e.includes('NOT IMPLEMENTED');
+        if (t === 'timeout') return e === 'TIMEOUT';
+        return false;
+      }).slice(0, 3);
+      for (const s of samples) console.log(`      ${s.s}/${s.n}: ${(s.e||'').slice(0, 120)}`);
+    }
 
     expect(results.length).toBeGreaterThanOrEqual(830);
     expect(passed).toBeGreaterThanOrEqual(420);