Expand usage of existing instances

[Anatoly03]

• Move game connection logic to field instead of inheritance f981f54
• Add Game.sendChat method ff9897c
• Add Game.selfId field (contains bots' self id after init) 806937b
• Fix process is not defined in browser environment 9bb3c7e

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Motivating Examples

import "dotenv/config"
import { LobbyClient } from "pixelwalker.js"

export const client = LobbyClient.withToken(process.env.token);
export const game = await client.connection(process.env.world_id);

game.connection.on('playerInitPacket', message => {
    game.sendChat(`Connected as ${game.selfId}!`)
})

connection.bind();