Better CrazyGames integration (#3055)

## Description:

Better integration with CrazyGames:

* Don't show login because accounts have not been integrated with
CrazyGames yet
* Integrate CG invite links & usernames
* Refactor match making logic to Matchmaking.ts
* Allow periods to support crazy game usernames
* Create a no-crazygames class that disabled elements when on crazygames

## Please complete the following:

- [x] I have added screenshots for all UI updates
- [x] I process any text displayed to the user through translateText()
and I've added it to the en.json file
- [x] I have added relevant tests to the test directory
- [x] I confirm I have thoroughly tested these changes and take full
responsibility for any bugs introduced

## Please put your Discord username so you can be contacted if a bug or
regression is found:

evan

src/client/LangSelector.ts

@@ -228,6 +228,7 @@ export class LangSelector extends LitElement {
       "stats-modal",
       "flag-input-modal",
       "flag-input",
+      "matchmaking-button",
       "token-login",
     ];