Identify a fence alternative by the table row rather than the cell, keep the outermost row through a reached table, and key reads and visits by it

node.go

@@ -66,6 +66,7 @@ type template struct {
 	record       bool        // compiled at the top without a repeat, so its fields are record columns
 	table        *table      // the table whose format this is, whose columns are the fields
 	cellOf       *table      // the table whose cell this is
+	cellRow      int         // the row the cell sits in
 	drawGroup    string      // the draw group it draws in, as written; "" keeps its caller's
 	drawGroupKey string      // its draw group keyed by its category once linked: what a render reads its reference paths under
 }