fix(deps): update temporal-polyfill to v1 and fix CJS build

build/build-cjs.js

@@ -1,9 +1,9 @@
 // Generate the CommonJS entry point (node-ical.cjs) from the ESM sources.
 //
 // ESM (*.js, type: module) is the single source of truth. This bundles
-// node-ical.js into a single self-contained CommonJS file so that
-// `require('node-ical')` keeps working, while runtime dependencies stay
-// external `require()` calls.
+// node-ical.js into a single CommonJS file so that `require('node-ical')` keeps
+// working. The Temporal polyfill is bundled because its v1 package is ESM-only;
+// rrule-temporal remains an external runtime dependency.
 import {build} from 'esbuild';
 
 await build({
@@ -14,8 +14,6 @@ await build({
   format: 'cjs',
   // Keep in sync with engines.node in package.json and node-version in .github/workflows/nodejs.yml
   target: 'node22',
-  // Keep node_modules dependencies as require() calls; only bundle our own code
-  // (and inline windowsZones.json, which is imported relatively).
-  packages: 'external',
+  external: ['rrule-temporal', 'rrule-temporal/totext'],
   logLevel: 'info',
 });

package.json

@@ -40,7 +40,7 @@
   },
   "dependencies": {
     "rrule-temporal": "^2.0.0",
-    "temporal-polyfill": "^0.3.2"
+    "temporal-polyfill": "^1.0.1"
   },
   "devDependencies": {
     "date-fns": "^4.4.0",

test/polyfill-check.test.js

@@ -1,5 +1,6 @@
 import assert from 'node:assert/strict';
 import {execSync} from 'node:child_process';
+import {readFileSync} from 'node:fs';
 import {describe, it} from 'mocha';
 
 describe('Temporal Polyfill Configuration', () => {
@@ -12,4 +13,20 @@ describe('Temporal Polyfill Configuration', () => {
       assert.ok(true, 'JSBI is not installed as expected');
     }
   });
+
+  it('should use temporal-polyfill v1 as a direct dependency', () => {
+    // Read the installed package's own package.json directly instead of
+    // shelling out to `npm ls`, which can exit non-zero (and make execSync
+    // throw) for unrelated dependency-tree issues.
+    const packageJsonUrl = new URL('../node_modules/temporal-polyfill/package.json', import.meta.url);
+    const {version} = JSON.parse(readFileSync(packageJsonUrl, 'utf8'));
+
+    assert.match(String(version), /^1\./v);
+  });
+
+  it('should load temporal-polyfill via ESM import', async () => {
+    const mod = await import('temporal-polyfill');
+
+    assert.ok(mod.Temporal, 'temporal-polyfill should expose Temporal');
+  });
 });