remove unused imports from wasm_bridge.go and add required imports to assets_wasm.go

cmd/client/assets_wasm.go

@@ -6,6 +6,8 @@ package main
 import (
 	_ "embed"
 	"encoding/json"
+	"fmt"
+	"log"
 	"path/filepath"
 
 	"github.com/hajimehoshi/ebiten/v2/ebitenutil"