feat: algorithm module with unit tests

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

package.json

@@ -2,6 +2,7 @@
   "name": "morning-meeting-planner",
   "version": "1.0.0",
   "private": true,
+  "type": "module",
   "scripts": {
     "start": "npx serve . -p 3000",
     "test": "node tests/algorithm.test.mjs"