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>

desk/lockscreen.go

@@ -14,7 +14,7 @@ import (
 type LockScreenOptions struct{}
 
 type LockScreenResult struct {
-	Element *ui.Element
+	Element ui.Element
 	// Unlocked is a key or click opening it this frame.
 	Unlocked bool
 }
@@ -40,7 +40,7 @@ func LockScreen(c *ui.Context, text string, open *bool, o LockScreenOptions) Loc
 			g.Text((g.W-pixel.Measure(press))/2, g.H-3*pixel.LineHeight, press, pixel.Accent, 1)
 		}
 	})
-	if panel != nil {
+	if panel.Valid() {
 		panel.Description(clock + ", " + date + ", " + press)
 	}
 	if woke {