⚡️ Performance: audit creating new objects in game logic

[JoshuaKGoldberg]

Feature Request Checklist

• I have tried restarting my IDE and the issue persists.
• I have pulled the latest main branch of the repository.
• I have searched for related issues and found none that matched my issue.

Overview

Browser GC (garbage collection) happens sporadically throughout a webpage's runtime and can cause little blips of bad performance. It's best to avoid creating new objects that will cause GC to have to run.

One common culprit is inline literals such as [] and {}. I know I've seen them at least in the timehandlr codebase. I should do an audit of where those are created and try to avoid them.

Additional Info

One common strategy is to use shared empty objects -- as long as nothing modifies them.

export const emptyArray = [] as const;
export const emptyObject = [] as const;