feat: add configurable speed and expanded grid presets for snake

- Add per-game speed setting with presets (Slow/Normal/Fast/Insane)
- Add speed selector UI in snake lobby
- Expand grid presets with Tiny (15x15) and XL (50x30)
- Auto-calculate cell size based on grid dimensions
- Preserve speed setting in rematch games

ui/lobby.go

@@ -21,6 +21,8 @@ type LobbyProps struct {
 	SnakeSoloClicks     []h.H
 	SnakeMultiClicks    []h.H
 	ActiveSnakeGames    []*snake.SnakeGame
+	SelectedSpeedIndex  int
+	SpeedSelectClicks   []h.H
 }
 
 func LobbyView(p LobbyProps) h.H {
@@ -41,7 +43,7 @@ func LobbyView(p LobbyProps) h.H {
 
 	var tabContent h.H
 	if p.ActiveTab == "snake" {
-		tabContent = SnakeLobbyTab(p.SnakeNicknameBind, p.SnakeSoloClicks, p.SnakeMultiClicks, p.ActiveSnakeGames)
+		tabContent = SnakeLobbyTab(p.SnakeNicknameBind, p.SnakeSoloClicks, p.SnakeMultiClicks, p.ActiveSnakeGames, p.SelectedSpeedIndex, p.SpeedSelectClicks)
 	} else {
 		tabContent = connect4LobbyContent(p)
 	}

ui/snakeboard.go

@@ -45,10 +45,7 @@ func SnakeBoard(sg *snake.SnakeGame) h.H {
 	}
 
 	// Cell size scales with grid dimensions
-	cellSize := 20
-	if state.Width <= 20 {
-		cellSize = 24
-	}
+	cellSize := cellSizeForGrid(state.Width, state.Height)
 
 	var rows []h.H
 	for y := 0; y < state.Height; y++ {
@@ -94,3 +91,22 @@ func SnakeBoard(sg *snake.SnakeGame) h.H {
 	attrs = append(attrs, rows...)
 	return h.Div(attrs...)
 }
+
+func cellSizeForGrid(width, height int) int {
+	maxDim := width
+	if height > maxDim {
+		maxDim = height
+	}
+	switch {
+	case maxDim <= 15:
+		return 28
+	case maxDim <= 20:
+		return 24
+	case maxDim <= 30:
+		return 20
+	case maxDim <= 40:
+		return 16
+	default:
+		return 14
+	}
+}

ui/snakelobby.go

@@ -7,7 +7,7 @@ import (
 	"github.com/ryanhamamura/via/h"
 )
 
-func SnakeLobbyTab(nicknameBind h.H, soloClicks, multiClicks []h.H, activeGames []*snake.SnakeGame) h.H {
+func SnakeLobbyTab(nicknameBind h.H, soloClicks, multiClicks []h.H, activeGames []*snake.SnakeGame, selectedSpeedIndex int, speedSelectClicks []h.H) h.H {
 	// Solo play buttons
 	var soloButtons []h.H
 	for i, preset := range snake.GridPresets {
@@ -56,6 +56,29 @@ func SnakeLobbyTab(nicknameBind h.H, soloClicks, multiClicks []h.H, activeGames
 		),
 	)
 
+	// Speed selector
+	var speedButtons []h.H
+	for i, preset := range snake.SpeedPresets {
+		btnClass := "btn btn-sm"
+		if i == selectedSpeedIndex {
+			btnClass += " btn-active"
+		}
+		var click h.H
+		if i < len(speedSelectClicks) {
+			click = speedSelectClicks[i]
+		}
+		speedButtons = append(speedButtons, h.Button(
+			h.Class(btnClass),
+			h.Type("button"),
+			h.Text(preset.Name),
+			click,
+		))
+	}
+	speedSelector := h.Div(h.Class("mb-4"),
+		h.Label(h.Class("label"), h.Text("Speed")),
+		h.Div(append([]h.H{h.Class("btn-group")}, speedButtons...)...),
+	)
+
 	soloSection := h.Div(h.Class("mb-6"),
 		h.H3(h.Class("text-lg font-bold mb-2"), h.Text("Play Solo")),
 		h.Div(append([]h.H{h.Class("flex gap-2 justify-center")}, soloButtons...)...),
@@ -93,6 +116,7 @@ func SnakeLobbyTab(nicknameBind h.H, soloClicks, multiClicks []h.H, activeGames
 
 	return h.Div(
 		nicknameField,
+		speedSelector,
 		soloSection,
 		multiSection,
 		gameListEl,