## Summary
- Implemented the Go API endpoint for Memory message forgetting:
- `DELETE /api/v1/messages/{memory_id}:{message_id}`
- Added route registration for the Memory message DELETE endpoint only.
- Added request path validation for `memory_id:message_id`.
- Added service logic to mark a message as forgotten by setting
`forget_at`.
- Preserved Python-compatible response behavior:
- Success returns `code: 0`, `message: true`, `data: null`.
- Added focused unit tests for message path parsing and invalid message
ID handling.
- Fixed Linux cgo linker config to use the installed shared PCRE2
library so Go tests/builds can run in this environment.
## Related Issue
Closes: #15240
## Change Type
- [x] Feature
- [x] Test
- [x] Build / CI compatibility
## Implemented API
- `DELETE /api/v1/messages/{memory_id}:{message_id}`
## Real Behavior Proof
Validated with targeted Go tests:
```bash
/tmp/go1.25.0/bin/go test ./internal/handler ./internal/router
```
Result:
```text
ok ragflow/internal/handler
? ragflow/internal/router [no test files]
```
Validated server entrypoint build:
```bash
/tmp/go1.25.0/bin/go build -o /tmp/ragflow-server-main ./cmd/server_main.go
```
Result:
```text
build succeeded
```
Validated patch formatting:
```bash
git diff --check
```
Result:
```text
no whitespace errors
```
## Checklist
- [x] Implemented only `DELETE
/api/v1/messages/{memory_id}:{message_id}`.
- [x] Did not implement unrelated Memory message APIs.
- [x] Added route registration.
- [x] Added handler validation.
- [x] Added service-level memory access check.
- [x] Added tests.
- [x] Ran targeted Go tests.
- [x] Ran server build validation.
- [x] Ran `git diff --check`.
## Summary
- Complete the Go Elasticsearch result functions that remained stubbed
after #15160.
- Add focused unit coverage for field mapping, aggregation, IDs, and
highlighting behavior.
- Update a stale query-builder test type import discovered during
validation.
## What changed
- Keep the Elasticsearch Go implementation merged in #15160 and fill in
`GetFields`, `GetAggregation`, `GetHighlight`, and `GetDocIDs` in
`internal/engine/elasticsearch/chunk.go`.
- Add regression and invariant coverage in
`internal/engine/elasticsearch/chunk_helpers_test.go`.
- Update `internal/service/nlp/query_builder_test.go` to use the current
`types.MatchTextExpr` type.
## Why
- #15160 implemented the main Go Elasticsearch surface, but
retrieval/tag flows still call result functions that returned stubs.
- Completing these functions keeps Elasticsearch result processing
aligned with the expected document-engine behavior for field extraction,
tag aggregation, doc ID extraction, and snippet highlighting.
## Validation
- `go test ./internal/engine/elasticsearch`
- `GOARCH=arm64 CGO_ENABLED=1 go test ./internal/service/nlp -run
TestQueryBuilder`
- `git diff --check`
- CodeRabbit review reported 0 issues after follow-up fixes.
- Codex Security diff scan found no reportable issues.
## Notes
- This PR is now a follow-up to #15160 rather than a competing
implementation.
- A full local `go test ./internal/service/nlp` run is blocked by local
WordNet resource prerequisites; the query-builder tests touched by this
PR pass with the arm64 CGO path.
