app/window,app/internal/window: allow min/max window size

The app.MinSize and app.MaxSize options restricts the window size:

w := app.NewWindow(
	app.Size(unit.Dp(600), unit.Dp(596)),
	app.MinSize(unit.Dp(600), unit.Dp(596)),
	app.MaxSize(unit.Dp(600), unit.Dp(596)),
	app.Title(APPNAME),
)

Signed-off-by: Jason <sourcehut@sweatyballs.es>

app/internal/window/window.go

@@ -14,8 +14,10 @@ import (
 )
 
 type Options struct {
-	Width, Height unit.Value
-	Title         string
+	Width, Height       unit.Value
+	MinWidth, MinHeight unit.Value
+	MaxWidth, MaxHeight unit.Value
+	Title               string
 }
 
 type FrameEvent struct {