Fix JSDoc @example hover when followed by code fence (#5167, #3107)

[AXT-AyaKoto]

Fixes #5167, Fixes #3107

When a JSDoc @example tag is immediately followed by a fenced code block, insert a newline before the content instead of — so markdown renders correctly in hover tooltips.

Example

The following JSDoc example is now rendered correctly.

/**
 * Double `n`.
 * 
 * @example
 * ```ts
 * 1 + 2
 * ```
 * 
 * @param n - The number you want to double
 * @returns a
 */
const double = (n: number): number => n * 2;

Expected rendering result (VSCode)	Latest Stable (Monaco Editor v0.55.1)	Correction result