Fix missing md extensions and update relative links

[HossamAbubakr]

Hello,

I have noticed that many relative links resulted in a github 404 page, after checking the markdown I noticed the following.

1. Several links are missing the md extension
2. Wrong relative links for nested files
3. Reference to non-exisiting files or files that are in a completely different folder (ex. how to contribute)

This pull request aims to mitigate only 1 and 2.
As I understand that everything is still WIP so 3 makes sense being as is for now.

Thank you

[DevGeniusCode]

If I remember correctly, the links were intentionally just filenames, to support internal wiki links and avoid opening the link on a new page.

[HossamAbubakr]

Oh interesting.

May I know what platform are you using as the wiki? As far as I know some systems allow the usage of extra syntax to specify the target.
Ex. {:target="_blank"}

[DevGeniusCode]

This repository is used to manage the content of the project's GitHub built-in wiki.

The wiki pages are version-controlled and stored as Markdown files within this repository.
When changes are merged into the main branch, the GitHub wiki is automatically synchronized with the latest content.

This approach allows for code review, collaboration, and version history of the documentation, while keeping the official GitHub wiki up to date.

You can view the live GitHub wiki here:
GeneralsGameCode Wiki
GeneralsGamePathc Wiki

[HossamAbubakr]

Oh! I must have missed it somehow.
Over there the links with extensions seem to work fine, in that case would you like me to revert the changes and keep the fixed "Builds" links or close the whole PR?