fix(template-require-mandatory-role-attributes): lowercase role in input-pair whitelist

ARIA role tokens compare ASCII-case-insensitively, so
`<input type="checkbox" role="SWITCH">` should qualify for the same
aria-checked exemption as `role="switch"`. Lowercases the role at the
whitelist-key boundary, matching the case-handling that already exists
for the `type` attribute. Mirrors jsx-a11y (`getExplicitRole` lowercases
role) and stays internally consistent with template-no-redundant-role.

Tests cover SWITCH/Switch/MENUITEMCHECKBOX/Radio/menuitemRadio on the
documented input-role pairings.

Author: johanrd

lib/rules/template-require-mandatory-role-attributes.js

@@ -56,10 +56,11 @@ function getInputType(node) {
 
 function isNativelyChecked(node, role) {
   const type = getInputType(node);
-  if (!type) {
+  if (!type || typeof role !== 'string') {
     return false;
   }
-  return NATIVELY_CHECKED_INPUT_ROLE_PAIRS.has(`${type}:${role}`);
+  // ARIA role tokens compare ASCII-case-insensitively.
+  return NATIVELY_CHECKED_INPUT_ROLE_PAIRS.has(`${type}:${role.toLowerCase()}`);
 }
 
 function getMissingRequiredAttributes(role, foundAriaAttributes, node) {

tests/lib/rules/template-require-mandatory-role-attributes.js

@@ -37,6 +37,14 @@ ruleTester.run('template-require-mandatory-role-attributes', rule, {
 
     // HTML `type` is ASCII case-insensitive; `Checkbox` must match `checkbox`.
     '<template><input type="Checkbox" role="switch" /></template>',
+
+    // ARIA role tokens are ASCII case-insensitive — mixed-case roles are
+    // exempted on the same pairings.
+    '<template><input type="checkbox" role="SWITCH" /></template>',
+    '<template><input type="checkbox" role="Switch" /></template>',
+    '<template><input type="CHECKBOX" role="MENUITEMCHECKBOX" /></template>',
+    '<template><input type="radio" role="Radio" /></template>',
+    '<template><input type="RADIO" role="menuitemRadio" /></template>',
   ],
 
   invalid: [
@@ -155,6 +163,14 @@ hbsRuleTester.run('template-require-mandatory-role-attributes', rule, {
 
     // HTML `type` is ASCII case-insensitive; `Checkbox` must match `checkbox`.
     '<input type="Checkbox" role="switch" />',
+
+    // ARIA role tokens are ASCII case-insensitive — mixed-case roles are
+    // exempted on the same pairings.
+    '<input type="checkbox" role="SWITCH" />',
+    '<input type="checkbox" role="Switch" />',
+    '<input type="CHECKBOX" role="MENUITEMCHECKBOX" />',
+    '<input type="radio" role="Radio" />',
+    '<input type="RADIO" role="menuitemRadio" />',
   ],
   invalid: [
     {