update the JavaScript version policy to ES2022 (after June 2027)

[erwindon]

Is your feature request related to a problem? Please describe.
Start using features from this JS version

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Start using useful features from this JS version.

The 13th edition, ECMAScript 2022, was published in June 2022. This version introduces top-level await, allowing the keyword to be used at the top level of modules; new class elements: public and private instance fields, public and private static fields, private instance methods and accessors, and private static methods and accessors; static blocks inside classes, to perform per-class evaluation initialization; the #x in obj syntax, to test for presence of private fields on objects; regular expression match indices via the /d flag, which provides start and end indices for matched substrings; the cause property on Error objects, which can be used to record a causation chain in errors; the at method for Strings, Arrays, and TypedArrays, which allows relative indexing; and Object.hasOwn, a convenient alternative to Object.prototype.hasOwnProperty.

Additional context
Update:

• docs/README.md (ecmaVersion)
• eslint.config.js
• any JS code