Close each owned os.Stdin file when replacing it in the stdin coverage
matrix so Windows TempDir cleanup does not fail on leaked handles. Update
the command registry coverage test for contract_identity source and drop
the retired loadPinnedMCPMetadata loader reference gate from policy.
Co-authored-by: Cursor <cursoragent@cursor.com>
Allow clearing interface_type and expanding constraint group members so
MCP-pin retirement and declare≡execute alias groups stay backward-compatible.
Close platform coverage gaps with TestCrossPlatformCoverage* and bump the
ContractFinal consistency count to 847.
Co-authored-by: Cursor <cursoragent@cursor.com>