refactor(admin-web): move answer markdown normalization to a tested lib

Extract normalizeLooseMarkdownLine from TrackingQuestionDetailView into
a shared monitoring-answer-markdown module and harden it (model bullet
`**-` and `*` handling). Add a vitest runner and unit tests for the
normalization rules.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

apps/admin-web/src/lib/monitoring-answer-markdown.test.ts

@@ -0,0 +1,26 @@
+import { describe, expect, it } from 'vitest'
+
+import { normalizeLooseMarkdownLine } from './monitoring-answer-markdown'
+
+describe('normalizeLooseMarkdownLine', () => {
+  it('turns a bold-prefixed model bullet into standard Markdown', () => {
+    expect(normalizeLooseMarkdownLine('**-拾光里家居**：15年本土营')).toBe(
+      '- **拾光里家居**：15年本土营',
+    )
+    expect(normalizeLooseMarkdownLine('  **- 拾光里家居**：15年本土营')).toBe(
+      '  - **拾光里家居**：15年本土营',
+    )
+  })
+
+  it('keeps ordinary bold text unchanged', () => {
+    expect(normalizeLooseMarkdownLine('**本地性价比高**，老板就在跑')).toBe(
+      '**本地性价比高**，老板就在跑',
+    )
+  })
+
+  it('keeps normalizing compact Markdown markers', () => {
+    expect(normalizeLooseMarkdownLine('-拾光里家居')).toBe('- 拾光里家居')
+    expect(normalizeLooseMarkdownLine('2.看封边')).toBe('2. 看封边')
+    expect(normalizeLooseMarkdownLine('##推荐清单')).toBe('## 推荐清单')
+  })
+})