feat: enhance group duty pin command functionality

- Updated the `pin_duty_cmd` to handle cases where no message ID is found by sending a new duty message, pinning it, saving the pin, and scheduling the next update.
- Improved error handling for message sending and pinning operations, providing appropriate replies based on success or failure.
- Enhanced unit tests to cover the new behavior, ensuring proper functionality and error handling in various scenarios.

webapp/vitest.config.js

@@ -0,0 +1,6 @@
+export default {
+  test: {
+    environment: "happy-dom",
+    include: ["js/**/*.test.js"],
+  },
+};