Wire the SessionLineage field on SessionSummary and CachedFile. The
relationship is captured ONLY when a provider writes it on disk in a
durable form: a child file that names its parent (Claude's
transcript-internal sessionId on a sidechain; Kimi Code's state.json
agents[<id>].parentAgentId for any non-main agent), or a parent file
whose spawn / child manifest names the children (Claude's
agentSpawnLinks; Kimi Code's state.json agents map listing any non-main
entry). The brief forbids inference from time adjacency or directory
layout, so a parent whose only evidence is the child file living under
its directory does not yet qualify, and stays lineage-less.
Per provider:
- claude: child (parentSessionId present) or root (agentSpawnLinks
non-empty). Captured at install time and through the append-merge in
scanProjectDirs, where lineage is sticky and cached-first.
- kimicode: child (parentAgentId === 'main') or root (sibling non-main
entry alongside the main agent). state.json is read by
kimicodeLineageForSource, called from the per-provider install path.
Bump PROVIDER_PARSE_VERSIONS for both providers to session-lineage-capture-v1
so already-cached sessions gain the new field on the next cold parse
(env fingerprint change forces the re-parse; the field is purely
additive, no cost / token / call total moves).
Invariant: byte-identical report totals with and without the field.
The new parser-lineage-capture test asserts this on a Claude corpus
(parent + two children) and covers Claude two-sided linkage, Claude
one-sided (child file names parent while parent's spawn result was
compacted away), Kimi Code nested subagent (child and root variants),
no-evidence (no lineage field at all, not 'unknown'), and the cache
round-trip across a warm-disk reload.
Co-authored-by: codeburn <dev@codeburn.local>
