feat(qwen-adapter): reject internal tab-container placeholder as answer

When Qwen returns an unresolved `[(tab_container_N)]` placeholder in
multiLoadIframe/barIframe content, treat it as an incomplete response:
fall back to a resolved sibling field when available, otherwise return
status `unknown` with a `qwen_incomplete_response` error so the record
is retried on a later collection pass instead of persisting garbage.

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

apps/desktop-client/src/main/adapters/qwen.ts

@@ -6,6 +6,7 @@ import { normalizeText } from './common'
 const QWEN_BOOTSTRAP_URL = 'https://www.qianwen.com/'
 const QWEN_PAGE_READY_TIMEOUT_MS = 20_000
 const QWEN_QUERY_TIMEOUT_MS = 90_000
+const QWEN_INTERNAL_TAB_PLACEHOLDER_PATTERN = /^(?:\[\(tab_container_\d+\)\]\s*)+$/i
 
 type QwenPageQuestionSnapshot = {
   model: string | null
@@ -200,6 +201,30 @@ function extractQuestionText(payload: Record<string, unknown>): string {
   throw new Error('qwen_question_text_missing')
 }
 
+function isQwenInternalPlaceholderOnly(value: unknown): boolean {
+  const text = normalizeOptionalString(value)
+  return Boolean(text && QWEN_INTERNAL_TAB_PLACEHOLDER_PATTERN.test(text))
+}
+
+function resolveQwenAnswerText(content: unknown): {
+  answerText: string | null
+  unresolvedPlaceholder: string | null
+} {
+  const candidates = [
+    readNestedString(content, ['multiLoadIframe', 'content']),
+    readNestedString(content, ['barIframe', 'content']),
+  ]
+  const answerText = candidates.find(
+    (candidate) => candidate && !isQwenInternalPlaceholderOnly(candidate),
+  )
+  const unresolvedPlaceholder = candidates.find(isQwenInternalPlaceholderOnly)
+
+  return {
+    answerText: answerText ?? null,
+    unresolvedPlaceholder: unresolvedPlaceholder ?? null,
+  }
+}
+
 function toJsonValue(value: unknown, depth = 0): JsonValue {
   if (value == null || depth > 16) {
     return null
@@ -630,10 +655,9 @@ export const qwenAdapter: MonitorAdapter = {
       }
     }
 
-    const answerText =
-      readNestedString(pageResult.answer.content, ['multiLoadIframe', 'content']) ??
-      readNestedString(pageResult.answer.content, ['barIframe', 'content']) ??
-      null
+    const { answerText, unresolvedPlaceholder } = resolveQwenAnswerText(
+      pageResult.answer.content,
+    )
     const requestId =
       normalizeText(pageResult.answer.reqId) ??
       readNestedString(pageResult.answer.communication, ['reqid']) ??
@@ -645,6 +669,21 @@ export const qwenAdapter: MonitorAdapter = {
     collectQwenSources(pageResult.answer.content, searchResults)
     const dedupedSearchResults = dedupeSourceItems(searchResults)
 
+    if (!answerText && unresolvedPlaceholder) {
+      return {
+        status: 'unknown',
+        summary: '千问仅返回内部内容占位符，未拿到完整答案，已回写 unknown 等待后续补采。',
+        error: buildAdapterError(
+          'qwen_incomplete_response',
+          'qwen returned an unresolved internal tab-container placeholder',
+          {
+            placeholder: unresolvedPlaceholder,
+            source_count: dedupedSearchResults.length,
+          },
+        ),
+      }
+    }
+
     if (!answerText && !dedupedSearchResults.length) {
       return {
         status: 'unknown',
@@ -689,4 +728,6 @@ export const qwenAdapter: MonitorAdapter = {
 
 export const __qwenTestUtils = {
   extractQuestionText,
+  isQwenInternalPlaceholderOnly,
+  resolveQwenAnswerText,
 }