Measure cross-chunk ore replay

internal/world/feature_scheduler.go

@@ -1,5 +1,7 @@
 package world
 
+import "fmt"
+
 // decorationSource is a source chunk whose feature pass may inspect or write a
 // target chunk. Vanilla FEATURES has a one-chunk block-state write radius.
 type decorationSource struct {
@@ -19,3 +21,21 @@ func decorationSources(targetX, targetZ int32) []decorationSource {
 	}
 	return sources
 }
+
+// replayScheduledOres replays each source center in deterministic order into a
+// shared region. The region must contain the target's radius-two base terrain;
+// source passes themselves may write only within their own radius-one window.
+// This is an explicit canonical order for isolated generation. It must not
+// replace the production path until parity evidence confirms that it matches
+// vanilla's chunk-status scheduling order.
+func (r *decorationRegion) replayScheduledOres(seed int64, targetX, targetZ int32) error {
+	for _, source := range decorationSources(targetX, targetZ) {
+		if err := r.setSource(source.X, source.Z); err != nil {
+			return err
+		}
+		if err := r.placeScheduledOres(seed); err != nil {
+			return fmt.Errorf("world: replay source (%d,%d): %w", source.X, source.Z, err)
+		}
+	}
+	return nil
+}