feat(pay): show 点击复制{copy name} tooltip on the remark button

Hovering the remark gave no affordance hint that it copies anything. The
reference theme titles the same button 点击复制{copy name} and omits the
tooltip entirely when no copy name is configured.

Emit data-toggle="tooltip" with that title on both copy buttons, gated on a
non-empty copy name, and mirror it on the paid-card helper so the two
surfaces agree. Bootstrap's tooltip init already runs in auto_fun() on load,
which is where the clipboard lib is required too.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

tests/widget-system/download-direct-contract.test.cjs

@@ -62,6 +62,18 @@ test('the download box renders direct anchors with inline extract codes', () =>
   // Mobile download bar scopes its own copy-button rule.
   assert.match(css, /\.resource-mobile-download-bar \.resource-download-box__btn--extract \{/);
 
+  // Hovering the remark shows 点击复制{copy name}, matching the reference theme,
+  // and only when a copy name exists.
+  assert.match(box, /\$has_copy && \$copy_key !== ''\) : \?>/);
+  assert.match(box, /sprintf\(__\('点击复制%s', 'aksrt'\), \$copy_key\)/);
+  assert.match(box, /data-toggle="tooltip"/);
+  const pay = read('inc/helpers/aksrt-pay.php');
+  assert.match(pay, /sprintf\(__\('点击复制%s', 'aksrt'\), \$copy_key\)/);
+  // Bootstrap tooltips must be initialized for the attribute to do anything.
+  const main = read('assets/js/runtime/main.js');
+  assert.match(main, /jQuery\("\[data-toggle='tooltip'\]"\)\.tooltip\(/);
+  assert.match(main, /^auto_fun\(\);/m);
+
   // The login gate keeps its own anchor.
   assert.match(box, /\$btn_href = \$login_url;/);
 });