tools.md: Remove unnecessary text, add table of contents, add hyperlinks to categories

[Annie-Wb]

I think tools.md requires some spring cleaning, and some improvements to make it easier for students to read and follow the instructions.

1. Some text, for example the part for distance learning, should be removed, as no courses currently give distance learning.
   Some text in the beginning also repeats what is already said.

2. A table of contents with all the different categories would be nice, so people don't have to scroll to find their device. That can be done with t.ex [Mac OS](#mac-os) (lower letters) to add hyperlinks to the specific category with that name.

[Annie-Wb]

Status update for this issue: tools.md

Changes:

1. Added TOC, hyperlinks. Refactored so that each category (Windows, MacOS, Linux) has all steps required to fully install all required tools.

2. Moved SDKMAN, Dual Booting and WSL to own categories.

3. Updated Hardware with more websites i personally can vouch for and 16GB ram requirement.

4. Updated from JDK 21 to JDK 25 as per latest LTS.

5. Kojo runs best with kojo.scala, other ones just complicate it for the student, kept it as the only option.

Left to do:

1. Ensure the whole document is congruent and there are no unnecessary repetitions.

2. Add more info about installing/setting up introprog API, TeXLive, etc as required later on in the course.