fix: support Unicode characters in form field names (#38138)

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

eslint-suppressions.json

@@ -1937,6 +1937,9 @@
   "web/app/components/base/markdown-blocks/form.tsx": {
     "no-restricted-imports": {
       "count": 1
+    },
+    "prefer-regex-literals": {
+      "count": 1
     }
   },
   "web/app/components/base/markdown-blocks/index.ts": {

web/app/components/base/markdown-blocks/__tests__/form.spec.tsx

@@ -532,6 +532,54 @@ describe('MarkdownForm', () => {
     })
   })
 
+  // Unicode letters should be valid form field names.
+  describe('Unicode name support', () => {
+    it('should include Unicode-named fields from all supported controls in JSON output', async () => {
+      const user = userEvent.setup()
+      const node = createRootNode(
+        [
+          createElementNode('label', { for: '用户名' }, [createTextNode('Username:')]),
+          createElementNode('input', { type: 'text', name: '用户名', value: 'Alice' }),
+          createElementNode('label', { for: '密码' }, [createTextNode('Password:')]),
+          createElementNode('input', { type: 'password', name: '密码', value: 'secret' }),
+          createElementNode('label', { for: '内容' }, [createTextNode('Content:')]),
+          createElementNode('textarea', { name: '内容', value: 'Hello' }),
+          createElementNode('label', { for: '日期' }, [createTextNode('Date:')]),
+          createElementNode('input', { type: 'date', name: '日期', value: dayjs('2026-01-10') }),
+          createElementNode('label', { for: '时间' }, [createTextNode('Time:')]),
+          createElementNode('input', { type: 'time', name: '时间', value: '09:00' }),
+          createElementNode('label', { for: '日期时间' }, [createTextNode('Datetime:')]),
+          createElementNode('input', { type: 'datetime', name: '日期时间', value: dayjs('2026-01-10T08:30:00') }),
+          createElementNode('label', { for: 'café' }, [createTextNode('Select:')]),
+          createElementNode('input', { type: 'select', name: 'café', value: 'hello', dataOptions: ['hello', 'world'] }),
+          createElementNode('input', { type: 'checkbox', name: '同意条款', value: true, dataTip: 'By checking this means you agreed' }),
+          createElementNode('button', { dataSize: 'small', dataVariant: 'primary' }, [createTextNode('Login')]),
+        ],
+        { dataFormat: 'json' },
+      )
+
+      render(<MarkdownForm node={node} />)
+
+      await user.click(screen.getByRole('button', { name: 'Login' }))
+
+      await waitFor(() => {
+        expect(mockOnSend).toHaveBeenCalled()
+      })
+
+      const submittedPayload = JSON.parse(mockOnSend.mock.calls[0]![0]) as Record<string, unknown>
+      expect(submittedPayload).toMatchObject({
+        用户名: 'Alice',
+        密码: 'secret',
+        内容: 'Hello',
+        日期: 'formatted-date',
+        日期时间: 'formatted-datetime',
+        café: 'hello',
+        同意条款: true,
+      })
+      expect(submittedPayload).toHaveProperty('时间')
+    })
+  })
+
   // Double-click protection: button disables after the first submit.
   describe('Double submit prevention', () => {
     it('should disable submit button after first click', async () => {

web/app/components/base/markdown-blocks/form.tsx

@@ -41,7 +41,15 @@ type SupportedType = typeof SUPPORTED_TYPES[keyof typeof SUPPORTED_TYPES]
 
 const SUPPORTED_TYPES_SET = new Set<string>(Object.values(SUPPORTED_TYPES))
 
-const SAFE_NAME_RE = /^[a-z][\w-]*$/i
+const SAFE_NAME_RE = (() => {
+  try {
+    return new RegExp('^\\p{L}[\\p{L}\\p{M}\\p{N}_-]*$', 'u')
+  }
+  catch {
+    // Fallback for browsers without Unicode property escape support.
+    return /^[a-z][\w-]*$/i
+  }
+})()
 const PROTOTYPE_POISON_KEYS = new Set(['__proto__', 'constructor', 'prototype'])
 
 function isSafeName(name: unknown): name is string {