Beatmapping portal/main page on wiki

[TheMoMan]

Related to #2615 I guess

One of the major criticisms we get about using the wiki as a resource for mapping is how difficult it is to navigate, find what you want, and discover new things. While we do have the main contents page on the wiki, mapping related pages are still rather scattered (e.g. editor documentation, ranking procedure, and mapping guides are all in different areas). As a result, we don't really have any good official resource we can link beginners to and just say "start here".

While there have been efforts over the past few years or so to significantly improve mapping related articles, they still may not be seen as much as we'd because they're hidden behind several layers of other articles and pages.

Wikipedia has a type of article called "portals" that act as a sort of "main page" for a specific topic. It would probably be pretty beneficial to build one of these on the topic of beatmapping. Not only would it help navigation for users, it could also help maintainers and writers consolidate what articles need to be written/improved, and also encourage new readers to also contribute.

tl;dr of above: Finding specific mapping pages is messy. Let's make a main mapping portal page to fix that.

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(draft) Categories to consolidate on the portal:

• Editor documentation
  • Getting started guide
  • tcm modes
• Mapping guides
  • External resources? (bnsite, youtube channels, etc)
• Mapping terminology and techniques
• Ranking procedure
  • Modding
  • Ranking criteria
  • BNs and NATs
• Beatmaps
  • Beatmap status (ranked, loved, etc)
  • Featured artists
  • Spotlights