fix(windows): observe settled claim loss

tools/tht/internal/safeio/private_root_windows.go

@@ -955,6 +955,23 @@ func windowsRelativeClaimAbsentOrOrphan(directory *windowsPrivateDirectory, sour
 
 const windowsClaimSharingRetries = 100
 
+func waitForWindowsRelativeClaimLoss(directory *windowsPrivateDirectory, source, claim string) (bool, error) {
+	for attempt := 0; ; attempt++ {
+		pair, pairErr := windowsRelativeClaimPairExists(directory, source, claim)
+		if pairErr == nil && pair {
+			return true, nil
+		}
+		absent, absentErr := windowsRelativeClaimAbsentOrOrphan(directory, source, claim)
+		if absentErr == nil && absent {
+			return true, nil
+		}
+		if attempt == windowsClaimSharingRetries {
+			return false, ErrUnsafeFile
+		}
+		time.Sleep(time.Millisecond)
+	}
+}
+
 func openWindowsPrivateClaimRegular(
 	directory windows.Handle,
 	name string,
@@ -988,12 +1005,8 @@ func (directory *windowsPrivateDirectory) ClaimRegular(source, claim string) (bo
 		1,
 	)
 	if err != nil {
-		pair, pairErr := windowsRelativeClaimPairExists(directory, source, claim)
+		lost, observationErr := waitForWindowsRelativeClaimLoss(directory, source, claim)
-		if pairErr == nil && pair {
+		if observationErr == nil && lost {
-			return false, nil
-		}
-		orphan, orphanErr := windowsRelativeClaimAbsentOrOrphan(directory, source, claim)
-		if orphanErr == nil && orphan {
 			return false, nil
 		}
 		return false, ErrUnsafeFile