reuse status dashboard message and simplify settings actions

src/status-dashboard.test.ts

@@ -0,0 +1,30 @@
+import fs from 'fs';
+import path from 'path';
+
+import { afterEach, describe, expect, it } from 'vitest';
+
+import { CACHE_DIR } from './config.js';
+import {
+  readDashboardStatusMessageId,
+  writeDashboardStatusMessageId,
+} from './status-dashboard.js';
+
+afterEach(() => {
+  const messagesDir = path.join(CACHE_DIR, 'status-dashboard', 'messages');
+  fs.rmSync(path.join(messagesDir, 'test-status-channel.json'), {
+    force: true,
+  });
+});
+
+describe('dashboard status message id state', () => {
+  it('persists the tracked Discord status message id across restarts', async () => {
+    expect(readDashboardStatusMessageId('test-status-channel')).toBeNull();
+
+    writeDashboardStatusMessageId('test-status-channel', '1499810000000000000');
+
+    expect(readDashboardStatusMessageId('test-status-channel')).toBe(
+      '1499810000000000000',
+    );
+    expect(readDashboardStatusMessageId('other-channel')).toBeNull();
+  });
+});