Inherited methods not merging JSDoc comments

## Steps to reproduce

```ts
class Foo {
/** foo bar */
method(): void {}
}

class Bar extends Foo {
/** @remarks lorem ipsum */
method(): void {}
}
```

## Behavior with `typescript@5.9`
Hovering over `Bar#method` gives:
```ts
(method) Bar.method(): void
foo bar
@remarks — lorem ipsum
```

## Behavior with `tsgo`
Hovering over `Bar#method` gives:
```ts
(method) Bar.method(): void
@remarks — lorem ipsum
```

Note that the `foo bar` is gone. I believe that blocks like `@remarks` being merged is a case not handled by microsoft/typescript-go#2111

Start with the TypeScript 5.9 and tsgo reproductions in the issue, then read microsoft/typescript-go#2111 for the related JSDoc merging behavior. Compare inherited method documentation handling, with completion meaning that the `foo bar` text and the `@remarks` block are merged consistently.

Written by the indexing model from the issue text.