## Problem
During ingestion, `indexdoc.ProcessChunksForPipeline` stamped
`ck["kb_id"]`
on every chunk. This was both:
- **a dead write** — `elasticsearch.InsertChunks` unconditionally
overwrites
the value with `datasetID` (`chunk.go:211`), so the producer's value
never
reached the index;
- **the wrong shape** — it was emitted as `[]string`, while both engines
actually need a single string.
This is the `kb_id` slice of the ingestion -> engine schema leak tracked
in
#17371: ingestion was carrying index-physical schema knowledge it should
not
own.
## Fix
Make the search engines the single owner of `kb_id` at the write
boundary,
and stop ingestion from emitting it:
- **Elasticsearch** (`chunk.go:211`) already sets `docCopy["kb_id"] =
datasetID`
— unchanged.
- **Infinity** (`chunk.go`) `InsertChunks` now stamps
`insertChunks[i]["kb_id"] = datasetID` right after
`transformChunkFields`
(previously it only *read/normalized* the producer value, which forced
ingestion to supply it). Both engines are now consistent.
- `ProcessChunksForPipeline` no longer stamps `kb_id` and the now-leaky
`kbID` parameter is removed. The same removal is propagated to
`ProcessPipelineOutputForGolden` and the `compare_pipeline_golden` dev
tool
(its `-kb-id` flag is dropped).
The stored `kb_id` value is byte-for-byte unchanged: `datasetID` passed
to
`InsertChunks` is `taskCtx.Doc.KbID`, i.e. the same id that was
previously
set on the producer chunk.
## Verification
- `bash build.sh --test ./internal/ingestion/task/indexdoc/...
./internal/engine/infinity/...`
— both green.
- `internal/ingestion/task` has **two pre-existing** failures
(`TestPipelineExecutor_Run_RealCanvasDSL_UsesGeneralPipeline`,
`TestRunPipeline_RealPipelineOutput_ProducesIndexFields`) that assert
`inserted chunk count = 1, want 2` — a parser/assertion mismatch (the Go
parser merges the 2-paragraph fixture into 1 chunk). They are unrelated
to
this change, which never touches chunk counting. The `kb_id`-related
test
failure this change would otherwise introduce is fixed by updating the
tests
below.
- Updated the pinning unit test:
`TestProcessChunksForPipeline_SetsDocID`
(formerly `...SetsDocIDAndKBID`) now asserts `kb_id` is **not** set by
the
producer. Removed the `kb_id` assertion and the now-dead
`taskChunkFieldEqualsStr` helper from
`pipeline_real_integration_test.go`.
## Scope
This closes only the `kb_id` portion of #17371. The remaining
index-physical
fields (`docnm_kwd`, `create_timestamp_flt`, `page_num_int`/`top_int`/
`position_int`, etc.) are intentionally left for a follow-up (P2).
