Adds CorrectionRequest, CorrectionResult, CorrectionMode,
CorrectionPatch, CorrectionDryRunReport, CorrectionNotFoundError,
and CorrectionConflictError domain models.
Implements CorrectionService with BFS-based revert (marks decisions
as rolled back and restores via inverse changes) and append mode
(spawns a child correction plan). Includes request_correction()
with dry-run support and dispatch_correction() convenience method.
33 Behave scenarios, 8 Robot smoke tests, ASV benchmark suite,
and reference documentation.
Ref: Day-14 Rebaseline – M4.2 Decision-correction flows [Jeff]
