Make web document navigation survive live-updating pages

Recreated-node caret recovery, tolerant caret validation, per-root retained document trees and cursors across tab switches, document warm-up, coalesced structural moves, and hung-provider fast-fail with an 'Application is not responding' announcement.

internal/atspi/adapter_tree_native.go

@@ -540,13 +540,8 @@ func (adapter *Adapter) invalidateReplacedDocument(sourceID, activeID ObjectID)
 	if !sourceID.Valid() || sourceID != activeID {
 		return
 	}
-	adapter.treeMutex.Lock()
-	trees := []*AccessibleTree{adapter.tree, adapter.documentTree, adapter.documentTextTree}
-	adapter.treeMutex.Unlock()
+	trees := adapter.ownedTrees()
 	for _, tree := range trees {
-		if tree == nil {
-			continue
-		}
 		root, err := tree.Root()
 		if err != nil || root.ID().BusName != sourceID.BusName {
 			continue
@@ -574,10 +569,23 @@ func (adapter *Adapter) invalidateTreeEventWithPolicy(eventType string, detail1
 			}
 		}
 	}
+	// Kinds parallel the historical slot indices: 0 review, 1 semantic
+	// document, 2 document text. Stashed documents repeat kinds 1 and 2.
 	adapter.treeMutex.Lock()
 	trees := []*AccessibleTree{adapter.tree, adapter.documentTree, adapter.documentTextTree}
+	kinds := []int{0, 1, 2}
+	for _, id := range adapter.stashedDocumentIDs {
+		stashed := adapter.stashedDocuments[id]
+		if stashed.tree != nil {
+			trees, kinds = append(trees, stashed.tree), append(kinds, 1)
+		}
+		if stashed.textTree != nil {
+			trees, kinds = append(trees, stashed.textTree), append(kinds, 2)
+		}
+	}
 	adapter.treeMutex.Unlock()
-	for index, tree := range trees {
+	for position, tree := range trees {
+		index := kinds[position]
 		if navigationDefunct && index == 1 && tree != nil {
 			tree.mu.RLock()
 			entry := tree.nodes[sourceID]