SOW-0047: reduce adapter mapper complexity

[ktsaou]

Summary

• Split the adapter mapper user, assistant, and snapshot paths into focused helpers.
• Added characterization tests for tool-result payload ownership, mixed op ordering, and snapshot metadata updates.
• Corrected the adapter behavior spec for historical assistant op ordering and recorded validation/review evidence in the active SOW.

Validation

• ./scripts/gates.sh
• local file-scoped static analysis: 0 issues on changed mapper files
• external review converged

---

Summary by cubic

Reduced complexity in the internal/adapters/claude_code mapper by splitting user, assistant, and snapshot mapping into focused helpers while keeping behavior, event order, and performance unchanged. Added characterization tests and corrected the adapter spec to reflect the historical assistant op ordering.

• Refactors
  • Decomposed mapper into ops_user.go, ops_assistant.go, and ops_snapshot.go with focused helpers; trimmed ops.go.
  • Preserved event order: LLM → all thinking ops → all tool_use ops; kept tool-result finalization and payload ref ownership (one ref per record on the first match).
  • Kept Agent tool_use as session ops with toolUseId stashed and child-session linking unchanged.
  • Added tests for tool-result payload ownership, mixed assistant op ordering, and snapshot metadata updates.
  • Corrected .agents/sow/specs/adapter-claude-code.md to document the real ordering; no API/schema/runtime changes; benchmarks unchanged.

^{Written for commit 3396721. Summary will update on new commits.}

[codacy-production]

Up to standards ✅

🟢 Issues 0 issues

Results:
0 new issues

View in Codacy

🟢 Metrics 75 complexity · 1 duplication

Metric	Results
Complexity	75
Duplication	1

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[cubic-dev-ai]

No issues found across 7 files

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