Add Discord client, command router and voice channel handling

internal/discord/commands.go

@@ -0,0 +1,15 @@
+package discord
+
+import (
+	"fmt"
+
+	"github.com/disgoorg/disgo/bot"
+	"github.com/disgoorg/disgo/discord"
+)
+
+func RegisterCommands(client *bot.Client, definitions []discord.ApplicationCommandCreate) error {
+	if _, err := client.Rest.SetGlobalCommands(client.ApplicationID, definitions); err != nil {
+		return fmt.Errorf("registering commands: %w", err)
+	}
+	return nil
+}