Add project components 421-435; Checkbox turns only when on

Fifteen project components: QuestBoard, TaskItem, TaskList, Milestones,
Burndown, Pomodoro, Priority, AssigneePicker, LabelPicker, TimeTracker,
Roadmap, SprintPanel, IssueCard, Checklist and WorkloadBar.

QuestBoard is one base that draws TODO, DOING and DONE; arrows move,
Alt with an arrow carries a card, and a drag carries it live. Priority
draws 12x12 bars, and Critical is on fire. Pomodoro banks time on PAUSE
and the tomato sleeps through the rest. Extreme inputs fail fast or
saturate instead of wrapping.

MyGo's CheckboxBase turns its value before Disabled is set, so
input.Checkbox now hands it a copy and keeps only turns of an enabled
base. The home scene test checks the sky row, not one pixel that
falling snow can cover.

project/issuecard.go

@@ -0,0 +1,95 @@
+package project
+
+import (
+	"log/slog"
+	"strings"
+
+	"github.com/egoist/mygo/ui"
+
+	"git.zacharyzhang.com/ZacharyZhang-NY/8bitMyGoUI/display"
+	"git.zacharyzhang.com/ZacharyZhang-NY/8bitMyGoUI/pixel"
+)
+
+// Issue is a bug or a wish, under an id.
+type Issue struct {
+	ID       string
+	Title    string
+	Labels   []Label
+	Assignee string
+	Priority Level
+}
+
+type IssueCardOptions struct {
+	// Width is in dots; zero means 160.
+	Width    int
+	Disabled bool
+}
+
+type IssueCardResult struct {
+	Element *ui.Element
+	Clicked bool
+}
+
+// IssueCard shows an issue's id, title, labels and assignee.
+func IssueCard(c *ui.Context, is Issue, o IssueCardOptions) IssueCardResult {
+	k := pixel.K(c)
+	if is.ID == "" || is.Title == "" {
+		panic("project: IssueCard needs an id and a title")
+	}
+	said := make([]string, 0, len(is.Labels)+2)
+	for _, l := range is.Labels {
+		if l.Name == "" {
+			panic("project: IssueCard has a label with no name")
+		}
+		said = append(said, l.Name)
+	}
+	who := is.Assignee
+	if who == "" {
+		who = k.Msg("nobody")
+	}
+	said = append(said, is.Priority.word(k), who)
+	w := pixel.Or("IssueCard Width", o.Width, 160)
+	lines := pixel.Wrap(is.Title, w-8, 2)
+	// The shell draws the card; the button stays bare.
+	shell, base, st := pixel.Shell(c, func() *ui.Element {
+		return ui.ButtonBase(c).Label(is.ID + " " + is.Title).Disabled(o.Disabled)
+	})
+	base.Description(strings.Join(said, ", "))
+	res := IssueCardResult{Element: shell, Clicked: base.Clicked()}
+	h := 3 + pixel.LineHeight*(len(lines)+2) + 6
+	shell.Size(k.D(w), k.D(h)).Draw(func(p *ui.Painter, r ui.Rect) {
+		g := k.Canvas(p, r)
+		fill := pixel.Face
+		if st.Hover {
+			fill = pixel.Lit
+		}
+		g.Frame(0, 0, w, h, pixel.Raised, fill)
+		g.Text(4, 3, is.ID, pixel.Faint, 1)
+		mark(g, w-16, 5, is.Priority, 1)
+		for i, l := range lines {
+			g.Text(4, 3+pixel.LineHeight*(i+1), l, pixel.Ink, 1)
+		}
+		// Labels run until the assignee's seat; the rest wait.
+		y, x := 3+pixel.LineHeight*(len(lines)+1)+2, 4
+		for _, l := range is.Labels {
+			cw := 10 + pixel.Measure(l.Name)
+			if x+cw > w-24 {
+				break
+			}
+			g.Rect(x, y+5, 7, 7, pixel.Edge)
+			g.Rect(x+1, y+6, 5, 5, l.Slot)
+			g.Text(x+10, y, l.Name, pixel.Faint, 1)
+			x += cw + 6
+		}
+		if is.Assignee == "" {
+			g.Veil(w-20, y, 16, 16, pixel.Shade, 8)
+		} else {
+			display.Face(g, w-20, y, is.Assignee, 1)
+		}
+		g.Finish(st)
+	})
+	if res.Clicked {
+		slog.Debug("8bit: issue card", "id", is.ID)
+	}
+	return res
+}