[Studio] feat(web): DLQ message details, selected resend and Excel export

[zhaohai666]

[Web] DLQ message details, selected re-send and Excel export

Summary

The studio DLQ page only offered group-level statistics, a time-window bulk re-delivery action and a
JSON export. Compared with the classic dashboard it was missing the two most-used operations:
browsing the individual dead-letter messages of a group, and re-sending a single / selected
batch of them. The JSON export also did not match the expected Excel format. This PR closes that gap.

Changes

Backend

• DLQProvider (interface) and DLQProviderStub: three new operations —
  listMessages (paged details), resendMessages by msgId list, and exportExcel.
• RocketMQDLQProvider:
  • listMessages scans the %DLQ%<group> topic with a pull consumer within the requested window
    and returns a PageResult<DLQMessageVO> (msgId, topic, queueId, offset, storeTime, keys, body).
  • resendMessages(msgIds, targetTopic) scans the DLQ topic, filters the selected messages by
    msgId and re-sends each to its origin topic (or an explicit target) with a short-lived producer,
    reusing the existing resendOne logic (including origin-topic property fallback).
  • exportExcel streams the same scan into a real .xlsx workbook.
• DLQController: three new endpoints —
  • GET /api/dlq/{groupName}/messages (paged details),
  • POST /api/dlq/resend-selected (by msgId list, optional targetTopic),
  • GET /api/dlq/export-excel (single message ids or the whole window, returns .xlsx).
• DLQService: validation + Apache-only guard (cloud instances keep 501), plus
  resendSelectedMessages and exportExcel delegation.
• New DLQMessageExcelRow (EasyExcel row model with formatted store time) and
  DLQResendSelectedRequestDTO.
• server/pom.xml: adds com.alibaba:easyexcel:2.2.10 for .xlsx generation.

Frontend

• api/message.ts: DLQMessage / DLQMessagePage types and listDLQMessages,
  resendDLQSelected, exportDLQExcel API functions.
• services/messageService.ts: service wrappers (with mock fallbacks).
• pages/instance/dlq.tsx:
  • The old "查看详情" stats dialog is replaced by a message detail drawer: paged table of
    dead-letter messages, row selection, single / batch re-send, and Excel export of the selection
    or the whole window.
  • The row-level "导出" action now downloads .xlsx instead of .json.

Tests

• RocketMQDLQProviderTest / DLQServiceTest / DLQControllerTest / DLQProviderStubTest:
  49 tests green, covering the new endpoints, paged detail validation and provider delegation.
• DLQPage.test.tsx: updated the detail-dialog case to assert the new drawer (including the
  listDLQMessages call) and the Excel export path (.xlsx download via the shared download util).

Validation

• Frontend: tsc -b clean; DLQPage.test.tsx (14) green.
• Backend: mvn -o checkstyle:check test -Dtest="RocketMQDLQProviderTest,DLQServiceTest,DLQControllerTest,DLQProviderStubTest" —
  49 tests green.

Notes

• The existing time-window bulk re-send and group-level CSV export are kept unchanged.
• Cloud instances still return 501 for DLQ detail / resend / Excel operations
  (requireApacheInstance guard), consistent with the rest of the DLQ feature.

[RockteMQ-AI]

LGTM — comprehensive feature that adds DLQ message listing, selective resend, and Excel export. The backend correctly uses EasyExcel for streaming export, and the frontend provides a clear UI with pagination and batch operations.

Good design: the resend-selected endpoint accepts specific message IDs instead of re-querying, and the Excel export supports both full export and filtered export by message IDs. Mock mode support is consistent with other features.

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Automated review by github-manager-bot

[RockteMQ-AI]

⚠️ Merge conflict detected

This PR has conflicts with the base branch and cannot be merged. Please rebase or merge the base branch into your branch and resolve the conflicts:

git fetch origin
git checkout feature/studio-dlq-detail
git rebase origin/rocketmq-studio
# resolve conflicts, then:
git push --force-with-lease

This is a one-time reminder. Feel free to @mention me for a re-review after conflicts are resolved.

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Automated notification by github-manager-bot

[RockteMQ-AI]

LGTM — re-approving after rebase. DLQ message details, selected resend and Excel export are well-structured.