feat(signals): decode recordings with bounded sigrok output (#2339)
Decode caller-selected protocols from existing recordings through shared
CLI/MCP Evidence. Page literal output lines after complete decoding;
preserve explicit full output, source identity and failed cleanup ownership.
Verified real sigrok-cli 0.7.2 workflows, published UART/SPI/I2C recordings,
independent UART values, selector limits, SDK schemas and cleanup regressions.
Co-authored-by: Olorinm <59321404+Olorinm@users.noreply.github.com>
Assisted-by: Kogasa (gensokyo-skills:kogasa-surprise-testing)