Function implementation name must be ... (2389) when abstract method is declared again later

### 🔎 Search Terms

duplicate abstract function declaration, abstract method, missing implementation, abstract method overload

### 🕗 Version & Regression Information

- This is the behavior in every version I tried, and I reviewed the FAQ for entries about abstract class

### ⏯ Playground Link

https://www.typescriptlang.org/play/?#code/IYIwzgLgTsDGEAJYBthjAgYge2wg3gFAIkKiQzwIBmArgHawAiApigIwAUAlAFwIA3bAEsAJgG5CxUnUasUAJh78Kw+gHMC00qSgsItKPQQByABbCT2hAF9r18tDiJZzNsi59BIiYTtA

### 💻 Code

```ts
abstract class Foo {
abstract func1(): void;

func2(): string {
// ^? Function implementation name must be 'func1'.(2389)
return 'hi'
}

abstract func1(): void;
}
```

### 🙁 Actual behavior

TS error reported for `func2`, which is valid.

### 🙂 Expected behavior

TS error reported for `func1`, which has duplicated abstract declaration.

### Additional information about the issue

_No response_

Reproduce the diagnostic using the TypeScript Playground link and the abstract class example in the issue. Trace how the compiler assigns implementation-name errors for repeated abstract declarations; done means the error points to the duplicated func1 declaration rather than the valid func2 implementation.

Written by the indexing model from the issue text.