Share section lookups and replacement previews across validators

internal/framework/validators/models.go

@@ -41,6 +41,8 @@ type Request struct {
 	RepairAttempt         *int                                   `json:"repair_attempt,omitempty"`
 	SectionIndex          *int                                   `json:"section_index,omitempty"`
 	WorkingTranscript     *schema.Transcript                     `json:"-"`
+	Section               *SectionLookup                         `json:"-"`
+	Previews              map[int]proposals.SegmentPreviewResult `json:"-"`
 	CandidateProposal     []proposals.EnrichedCorrectionProposal `json:"candidate_proposals"`
 	ModuleKey             string                                 `json:"module_key"`
 	ModuleInstance        string                                 `json:"module_instance"`