feat: noUnnecessaryCoalescingOperator for TypeScript

[rsiebertdev]

For those using the prefer-nullish-coalescing rule derived from typescript-eslint (still yet to be implemented), it'd be very nice to see Biome support a noUnnecessaryCoalescingOperator rule.

Take an example like this:

const value: string = "foo";
console.log(value ?? "bar");

🚨 This code will never produce bar in its output.

💭 This is because a string can only ever be truthy or falsy, and can never be nullish. This is something that, to my knowledge, is not yet checked by any major IDE's or linters.

---

Code like this could easily fall into production code, especially when using a rule like prefer-nullish-coalescing, and can be quite difficult to diagnose.

👉 Having a rule like noUnnecessaryCoalescingOperator would help to prevent this.