Add overlay components 176-195; pixel Harbor and Kit.Cue

Dialogs on DialogBase with focusable panels that harbor parked focus,
popovers on PopoverBase, bubbles, drawers, sheets, a lightbox, an RPG
dialogue box, notifications, a pause menu and a dithered title card.
Kit.Cue moves from feedback to pixel.

overlay/dialog.go

@@ -0,0 +1,69 @@
+package overlay
+
+import (
+	"log/slog"
+
+	"github.com/egoist/mygo/ui"
+
+	"git.zacharyzhang.com/ZacharyZhang-NY/8bitMyGoUI/input"
+	"git.zacharyzhang.com/ZacharyZhang-NY/8bitMyGoUI/layout"
+	"git.zacharyzhang.com/ZacharyZhang-NY/8bitMyGoUI/pixel"
+)
+
+type DialogOptions struct {
+	// Actions label buttons under the content; any one closes.
+	Actions []string
+	// Width is the window's in dots; zero means 220.
+	Width    int
+	Disabled bool
+}
+
+type DialogResult struct {
+	// Element is the window, nil while closed.
+	Element *ui.Element
+	// Action is the button clicked this frame, or -1.
+	Action int
+	// Closed is Escape or a click outside.
+	Closed bool
+}
+
+// Dialog is a titled window over a checkered backdrop.
+func Dialog(c *ui.Context, title string, open *bool, o DialogOptions, content func()) DialogResult {
+	k := pixel.K(c)
+	w := pixel.Or("Dialog Width", o.Width, 220)
+	was := *open
+	res := DialogResult{Action: -1}
+	res.Element = ui.DialogBase(c, open, func(back, panel *ui.Element) {
+		dim(k, back, pixel.Back, 8)
+		// The panel holds the focus when nothing inside can.
+		panel.Width(k.D(w)).Label(title).Focusable().FocusRing(false).Children(func() {
+			pixel.Harbor(c, panel, func() {
+				layout.Window(c, layout.WindowOptions{Title: title}, func() {
+					ui.Column(c).Gap(k.D(6)).AlignItems(ui.Stretch).Children(func() {
+						body(c, o.Disabled, content)
+						actions(c, o.Actions, o.Disabled, func(i int) { res.Action, *open = i, false })
+					})
+				})
+			})
+		})
+	})
+	res.Closed = was && !*open && res.Action < 0
+	if res.Action >= 0 || res.Closed {
+		slog.Debug("8bit: dialog", "title", title, "action", res.Action, "closed", res.Closed)
+	}
+	return res
+}
+
+// actions lines buttons up at the right; act takes clicks.
+func actions(c *ui.Context, labels []string, disabled bool, act func(i int)) {
+	if len(labels) == 0 {
+		return
+	}
+	ui.Row(c).Gap(pixel.K(c).D(4)).Justify(ui.End).Children(func() {
+		for i, l := range labels {
+			if input.Button(c, l, input.ButtonOptions{Size: input.Small, Disabled: disabled}).Clicked {
+				act(i)
+			}
+		}
+	})
+}