fix: use temporal-polyfill via npm overrides to resolve JSBI issues

package.json

@@ -21,9 +21,11 @@
     "node": ">=18"
   },
   "dependencies": {
-    "@js-temporal/polyfill": "^0.5.1",
     "rrule-temporal": "^1.4.5"
   },
+  "overrides": {
+    "@js-temporal/polyfill": "npm:temporal-polyfill@^0.3.0"
+  },
   "devDependencies": {
     "date-fns": "^4.1.0",
     "dayjs": "^1.11.19",
@@ -45,7 +47,8 @@
       "no-useless-catch": "off",
       "promise/prefer-await-to-then": "off",
       "unicorn/prefer-module": "off",
-      "unicorn/prefer-spread": "off"
+      "unicorn/prefer-spread": "off",
+      "import-x/no-extraneous-dependencies": "off"
     }
   },
   "scripts": {

test/polyfill-check.test.js

@@ -0,0 +1,39 @@
+const assert = require('node:assert/strict');
+const {execSync} = require('node:child_process');
+const path = require('node:path');
+const {describe, it} = require('mocha');
+
+describe('Temporal Polyfill Configuration', () => {
+  it('should NOT have JSBI dependency installed', () => {
+    try {
+      execSync('npm ls jsbi --json', {encoding: 'utf8', stdio: 'pipe'});
+      assert.fail('JSBI should not be installed');
+    } catch {
+      // Expected: JSBI should not be found (command will fail)
+      assert.ok(true, 'JSBI is not installed as expected');
+    }
+  });
+
+  it('should use temporal-polyfill (not @js-temporal/polyfill with JSBI)', () => {
+    const result = execSync('npm ls @js-temporal/polyfill --json', {encoding: 'utf8'});
+    const data = JSON.parse(result);
+
+    // Find the actual resolved package
+    const resolved = data.dependencies['rrule-temporal'].dependencies['@js-temporal/polyfill'];
+
+    assert.ok(resolved, '@js-temporal/polyfill should be resolved');
+    assert.match(resolved.resolved, /temporal-polyfill/);
+  });
+
+  it('should load temporal-polyfill when requiring @js-temporal/polyfill', () => {
+    // Clear require cache to force fresh load
+    const modulePath = require.resolve('@js-temporal/polyfill');
+    delete require.cache[modulePath];
+
+    const _Temporal = require('@js-temporal/polyfill');
+    const packageJsonPath = path.join(path.dirname(modulePath), 'package.json');
+    const packageJson = require(packageJsonPath);
+
+    assert.strictEqual(packageJson.name, 'temporal-polyfill');
+  });
+});