Update via to v0.4.0 and decouple tick rate from snake speed

Use via.OnKeyDownMap for snake keybindings, replacing the manual
dataExpr/rawDataAttr workaround. Window-scoped key handling removes
the need for tabindex/focus hacks, and WithPreventDefault on arrow
keys prevents page scrolling during gameplay.

Introduce a 60 FPS tick loop with a separate snake movement speed
(7 cells/s) so direction input is polled every frame but game state
only advances at the configured rate.

go.mod

@@ -5,8 +5,9 @@ go 1.25.4
 require (
 	github.com/google/uuid v1.6.0
 	github.com/pressly/goose/v3 v3.26.0
-	github.com/ryanhamamura/via v0.3.1
+	github.com/ryanhamamura/via v0.4.0
 	golang.org/x/crypto v0.47.0
+	maragu.dev/gomponents v1.2.0
 	modernc.org/sqlite v1.44.0
 )
 
@@ -42,7 +43,6 @@ require (
 	golang.org/x/sync v0.18.0 // indirect
 	golang.org/x/sys v0.40.0 // indirect
 	golang.org/x/time v0.14.0 // indirect
-	maragu.dev/gomponents v1.2.0 // indirect
 	modernc.org/libc v1.67.4 // indirect
 	modernc.org/mathutil v1.7.1 // indirect
 	modernc.org/memory v1.11.0 // indirect