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>

code/breakpoints.go

@@ -16,7 +16,7 @@ type BreakpointsOptions struct {
 }
 
 type BreakpointsResult struct {
-	Element *ui.Element
+	Element ui.Element
 	Changed bool
 }
 

code/codeblock.go

@@ -18,7 +18,7 @@ type CodeBlockOptions struct {
 }
 
 type CodeBlockResult struct {
-	Element *ui.Element
+	Element ui.Element
 	Copied  bool
 }
 

code/commandhistory.go

@@ -17,7 +17,7 @@ type CommandHistoryOptions struct {
 }
 
 type CommandHistoryResult struct {
-	Element *ui.Element
+	Element ui.Element
 	// Rerun is Enter or a double click on a command.
 	Changed, Rerun bool
 }

code/crashscreen.go

@@ -16,7 +16,7 @@ type CrashScreenOptions struct {
 }
 
 type CrashScreenResult struct {
-	Element  *ui.Element
+	Element  ui.Element
 	Continue bool
 }
 

code/debuggrid.go

@@ -14,7 +14,7 @@ type DebugGridOptions struct {
 }
 
 // DebugGrid rules content with the dot grid and rulers.
-func DebugGrid(c *ui.Context, o DebugGridOptions, content func()) *ui.Element {
+func DebugGrid(c *ui.Context, o DebugGridOptions, content func()) ui.Element {
 	k := pixel.K(c)
 	step := pixel.Or("DebugGrid Step", o.Step, 8)
 	if step < 2 || step > 32 {

code/diffview.go

@@ -20,7 +20,7 @@ type change struct {
 }
 
 // DiffView marks lines removed with -, added with +.
-func DiffView(c *ui.Context, text, before, after string, o DiffViewOptions) *ui.Element {
+func DiffView(c *ui.Context, text, before, after string, o DiffViewOptions) ui.Element {
 	k := pixel.K(c)
 	changes := diff(strings.Split(tidy(before), "\n"), strings.Split(tidy(after), "\n"))
 	// Rows share the longest width, so tints line up.

code/fpsmeter.go

@@ -16,7 +16,7 @@ type FPSMeterOptions struct {
 }
 
 // FPSMeter draws frame times as bars, newest right, with percentiles.
-func FPSMeter(c *ui.Context, text string, frames []time.Duration, o FPSMeterOptions) *ui.Element {
+func FPSMeter(c *ui.Context, text string, frames []time.Duration, o FPSMeterOptions) ui.Element {
 	k := pixel.K(c)
 	w, h := pixel.Or("FPSMeter Width", o.Width, 120), pixel.Or("FPSMeter Height", o.Height, 40)
 	for _, f := range frames {

code/glyphmap.go

@@ -16,7 +16,7 @@ type GlyphMapOptions struct {
 }
 
 type GlyphMapResult struct {
-	Element *ui.Element
+	Element ui.Element
 	Changed bool
 }
 

code/guards_test.go

@@ -115,9 +115,9 @@ func TestCrashScreenStepsAtFourFPS(t *testing.T) {
 	tt := view(600, 300, wd, func(c *ui.Context) {
 		code.CrashScreen(c, "panic: oops", nil, code.CrashScreenOptions{})
 	})
-	// Paint asks for the next step on the real clock.
+	// Paint asks for the next step on the frame clock.
 	pixel.ResetDue()
-	before := time.Now()
+	before := tt.Now()
 	tt.Frame()
 	if d := pixel.Due().Sub(before); d < time.Second/4 || d >= time.Second/2 {
 		t.Fatalf("the next blink step is %v away, want a quarter second", d)

code/hexviewer.go

@@ -16,7 +16,7 @@ type HexViewerOptions struct {
 }
 
 type HexViewerResult struct {
-	Element *ui.Element
+	Element ui.Element
 	Changed bool
 }
 

code/logviewer.go

@@ -40,7 +40,7 @@ type LogViewerOptions struct {
 }
 
 type LogViewerResult struct {
-	Element *ui.Element
+	Element ui.Element
 	// Changed is the level filter.
 	Changed bool
 }

code/memorymap.go

@@ -21,7 +21,7 @@ type MemoryMapOptions struct {
 }
 
 // MemoryMap draws each bank as a block filled by use.
-func MemoryMap(c *ui.Context, text string, banks []Bank, o MemoryMapOptions) *ui.Element {
+func MemoryMap(c *ui.Context, text string, banks []Bank, o MemoryMapOptions) ui.Element {
 	k := pixel.K(c)
 	cols := pixel.Or("MemoryMap Columns", o.Columns, 4)
 	for _, b := range banks {

code/paletteeditor.go

@@ -16,7 +16,7 @@ type PaletteEditorOptions struct {
 }
 
 type PaletteEditorResult struct {
-	Element *ui.Element
+	Element ui.Element
 	Changed bool
 }
 

code/pixeleditor.go

@@ -27,7 +27,7 @@ type PixelEditorOptions struct {
 }
 
 type PixelEditorResult struct {
-	Element *ui.Element
+	Element ui.Element
 	// Changed is the art; Copied is COPY.
 	Changed, Copied bool
 }
@@ -129,7 +129,7 @@ func PixelEditor(c *ui.Context, text string, art *string, o PixelEditorOptions)
 }
 
 // canvas paints cells, checkers where clear, grid and cursor.
-func canvas(shell *ui.Element, k pixel.Kit, st pixel.State, cells []int, w, z, cur int, grid bool) {
+func canvas(shell ui.Element, k pixel.Kit, st pixel.State, cells []int, w, z, cur int, grid bool) {
 	shell.Draw(func(p *ui.Painter, r ui.Rect) {
 		g := k.Canvas(p, r)
 		for i, v := range cells {

code/profilerbars.go

@@ -25,7 +25,7 @@ type ProfilerBarsOptions struct {
 var depths = []pixel.Slot{pixel.Accent, pixel.Info, pixel.Good, pixel.Warn, pixel.Magic}
 
 // ProfilerBars stacks spans under their parents, each bar its time.
-func ProfilerBars(c *ui.Context, text string, root Span, o ProfilerBarsOptions) *ui.Element {
+func ProfilerBars(c *ui.Context, text string, root Span, o ProfilerBarsOptions) ui.Element {
 	k := pixel.K(c)
 	w := pixel.Or("ProfilerBars Width", o.Width, 240)
 	if root.Length <= 0 {

code/registerview.go

@@ -27,7 +27,7 @@ type seen struct {
 const flags = "NV-BDIZC"
 
 // RegisterView shows registers and flags; the last change lights.
-func RegisterView(c *ui.Context, text string, cpu CPU, o RegisterViewOptions) *ui.Element {
+func RegisterView(c *ui.Context, text string, cpu CPU, o RegisterViewOptions) ui.Element {
 	k := pixel.K(c)
 	col := ui.Column(c).Gap(k.D(1)).Role(ui.RoleGroup).Label(text)
 	sn := ui.Local(col, regKey{}, func() seen { return seen{cpu: cpu} })

code/shortcutlist.go

@@ -22,7 +22,7 @@ type ShortcutListOptions struct {
 }
 
 // ShortcutList pairs actions with their keycaps.
-func ShortcutList(c *ui.Context, label string, items []Shortcut, o ShortcutListOptions) *ui.Element {
+func ShortcutList(c *ui.Context, label string, items []Shortcut, o ShortcutListOptions) ui.Element {
 	k := pixel.K(c)
 	for _, it := range items {
 		if len(it.Keys) == 0 {

code/spritesheet.go

@@ -23,7 +23,7 @@ type SpriteSheetOptions struct {
 }
 
 type SpriteSheetResult struct {
-	Element *ui.Element
+	Element ui.Element
 	// Changed is a frame chosen or play pressed.
 	Changed bool
 }

code/terminal.go

@@ -19,7 +19,7 @@ type TerminalOptions struct {
 }
 
 type TerminalResult struct {
-	Element *ui.Element
+	Element ui.Element
 	// Ran is the command Enter sent, else "".
 	Ran     string
 	Changed bool