Hardened the proposal modules to skip malformed proposals rather than hard failing the entire run

internal/framework/validators/models.go

@@ -18,6 +18,8 @@ const (
 	ReasonEmptyCorrectedText    = "empty_corrected_text"
 	ReasonNoEffect              = "no_effect"
 	ReasonProtectedGlossaryTerm = "protected_glossary_term"
+	ReasonValidatorMalformed    = "validator_malformed_response"
+	ReasonValidatorMissing      = "validator_missing_decision"
 )
 
 // Request is the runtime input shared by deterministic validators.