- _build_anchor_index(): regex-harvests PR/issue numbers, SHAs, branches,
file paths, error strings, handles, URLs from the compacted region into a
bounded indexed summary section. LLM-free, so needle identifiers cannot be
paraphrased away (the GUI-lineage failure class: 10/15 verbatim-or-nothing
golds). Doubles as session_search query-anchor map.
- evals/compaction/test_region_scoping.py: sentinel tripwire proving the
summarizer input carries ONLY the compacted region (head/tail sentinels
never reach the serialized turns body) in both legacy and lean modes.
c4bbb14e52