- Excluded signed `thinking` blocks and `redactedThinking` blobs from size-based persistence truncation.
- Preserved signature-bound reasoning verbatim to prevent provider validation failures on session replay.
- Maintained normal truncation behavior for unsigned thinking and standard text blocks.
- Implement cleanup logic to drop `thinkingSignature` values from assistant thinking blocks during persistence.
- Identify and drop signatures only when the underlying reasoning data is already recoverable via the `providerPayload` items.
- Ensure orphaned signatures that cannot be reconstructed from the payload are preserved during serialization.
- Add comprehensive test coverage to verify deduplication safety and edge-case handling for missing payloads.
can1357