feat: refine codex live chat context flows

etc/servers/work-server/src/routes/chat.test.ts

@@ -0,0 +1,13 @@
+import assert from 'node:assert/strict';
+import test from 'node:test';
+import { resolveStaticContentType } from './chat.js';
+
+test('resolveStaticContentType returns html content type for chat resource html files', () => {
+  assert.equal(resolveStaticContentType('/tmp/sample.html'), 'text/html; charset=utf-8');
+  assert.equal(resolveStaticContentType('/tmp/sample.htm'), 'text/html; charset=utf-8');
+});
+
+test('resolveStaticContentType keeps plain text content type for code resources', () => {
+  assert.equal(resolveStaticContentType('/tmp/sample.ts'), 'text/plain; charset=utf-8');
+  assert.equal(resolveStaticContentType('/tmp/sample.diff'), 'text/plain; charset=utf-8');
+});