Upgrade MyGo to v0.5.5

Elements are now pass-scoped value handles: tests that read bounds
after a frame bind a ui.Handle. pixel tells frames apart by the build
pass's root, since the Tester clock no longer moves on its own.

Fix the regressions the upgrade brought:
- Clipboard reads in input handlers go through c.Services().
- MyGo notes an overlay's opener after building it, so AutoFocus
  inside lost it; pixel.AutoFocus focuses through a Handle, and
  archtest bans the raw call. Dialogs hand the focus back again.
- Elements around a press stay hovered: Tooltip tells a press-given
  focus by focus arriving under the pointer.
- The web host moves the Tester clock with real time, at most 500 ms
  a call, and gives components the real clock.

The gallery's source index also accepts CRLF checkouts.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

data/infinitelist.go

@@ -17,7 +17,7 @@ type InfiniteListOptions struct {
 }
 
 type InfiniteListResult struct {
-	Element *ui.Element
+	Element ui.Element
 	// More asks for rows past the n there are.
 	More bool
 }
@@ -42,7 +42,7 @@ func InfiniteList(c *ui.Context, text string, n int, o InfiniteListOptions, row
 	if o.Done {
 		rows = n
 	}
-	var e *ui.Element
+	var e ui.Element
 	box.Children(func() {
 		e = ui.List(c, &s.list, rows, pixel.Lazy(c, func(i int) {
 			if i < n {