SSPICE 0.1.0 (CRAN resubmission)

• Removed direct assignment to .GlobalEnv in record correction. Per-record seeds now use withr scopes that restore the caller’s RNG state and kind, including on errors. Seeds remain deterministic across workers and batches.
• Replaced superassignment in routing diagnostics, logical-edit repair and admissible-pattern counting with explicit, per-call local environments.
• Random sequences differ from the previous submission. Checkpoint fingerprints now include the RNG scheme version, preventing reuse of old checkpoints.
• Added an internal null-default operator for compatibility with the declared R >= 4.2 requirement (the base operator is only available from R 4.4).