C_obs residual diagnostic and K_eff_v3 candidate-tension audit in a classified SPARC subset

This release provides a reproducible technical package for the C_obs residual diagnostic and K_eff_v3 candidate-tension audit in a classified SPARC subset. The package includes derived C_obs profile tables, K_eff_tail_v3 audit tables, calibrated Monte Carlo outputs, source-closure summaries, claim-boundary documentation, technical reports in English and Italian, reference code, configuration files, manifests, and checksums. The analysis distinguishes four scopes: 1. C_obs derived profiles for 175 SPARC galaxies;2. a classified diagnostic subset of 47 galaxies for K_eff_tail_v3 audit;3. a compact error-propagation pilot;4. a final full numerical Monte Carlo run on three source-cautioned candidate tensions: ESO563-G021, NGC5371, and NGC6195. The three K_eff_v3 cases are full-MC-stable source-cautioned candidate tensions. They are not clean failures and not strong K_eff claims. C_obs is treated as an operational residual diagnostic, not as proof of a new fundamental physical field. K_eff_tail_v3 is treated as a heuristic audit proxy, not as an independently validated physical predictor. This updated version additionally includes the Round 87 / Round 87b fixed documentation and protocol addendum. The added material provides a review-ready DOCX/PDF package, a data-availability statement, a canonical-units requirement, and a BIG-SPARC-ready ingestion protocol template. The Round 87b fixed addendum introduces no new scoring, no refit, and no new model branch. BIG-SPARC is retained as a primary planned external validation target, but no BIG-SPARC scores are reported here because the required CORBS-ready fields, canonical-unit conversion metadata, and/or stable release products were not available for a reproducible scoring run at the time of this package. Release version: v1.5.3Previous release DOI: 10.5281/zenodo.20342838Creator ORCID: 0009-0001-8032-7163