Add achievements to base game

- Add a script to generate achievement data from Steamworks API
- Add achievements page with a link in sidebar
- Calculate achievements (1/min) with an engine counter
- Store achievements with a timestamp on unlocked in the PlayerObject
- Add a script to generate monochrome icons from Steam icons
- Add toast when unlocking an achievement

src/Achievements/README.md

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+# Adding Achievements
+
+* Add a .svg in `./assets/Steam/achievements/real`
+* Create the achievement in Steam Dev Portal
+* Run `sh ./assets/Steam/achievements/pack-for-web.sh`
+* Run `node ./tools/fetch-steam-achievements-data DEVKEYHERE`
+  * Get your key here: https://steamcommunity.com/dev/apikey
+* Add an entry in `./src/Achievements/Achievements.ts` -> achievements
+* Commit `./dist/icons/achievements` & `./src/Achievements/AchievementData.json`