* fix: remap session JSONL chunk line numbers to original source positions
buildSessionEntry() flattens JSONL messages into plain text before
chunkMarkdown() assigns line numbers. The stored startLine/endLine
values therefore reference positions in the flattened text, not the
original JSONL file.
- Add lineMap to SessionFileEntry tracking which JSONL line each
extracted message came from
- Add remapChunkLines() to translate chunk positions back to original
JSONL lines after chunking
- Guard remap with source === "sessions" to prevent misapplication
- Include lineMap in content hash so existing sessions get re-indexed
Fixes#12044
* memory: dedupe session JSONL parsing
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Co-authored-by: Tak Hoffman <781889+Takhoffman@users.noreply.github.com>
