Move topics away from Wikipedia

[ceolinwill]

Is your feature request related to a problem? Please describe.
Right now, our topics are attached to Wikipedia. That means we're using Wikipedia API for searching and creating topics. That also means we cannot create a topic if it doesn't exist on Wikipedia.

That's good for standardizing topic names and to avoid vandalism/spam. However, that brings some problems because some topic names aren't available on Wikipedia. Even if we want to create a page on Wikipedia, that's not very straightforward because we're subject to their own rules.

For example, some time ago I wanted to create some lessons teaching Next.js - the web framework we're using for developing Zoonk. However, the Next.js page on Wikipedia wasn't approved by Wikipedia moderators based on the notability criteria (meaning their moderators think Next.js isn't notable enough to be on Wikipedia even though they allow a page about Nuxt.js, which is a similar framework).

So, I think it's not good for Zoonk in the long-term to be subject to arbitrary moderation rules created by Wikipedia moderators.

Describe the solution you'd like

The topic creation feature should be independent from Wikipedia. We should allow users to create/search topics directly on Zoonk.

Additional context

There's some extra work to make it work properly:

• We need to replace the current search
• We need to account for unexisting topics (i.e. users should be able to easily create new topics while searching for a topic name)
• We need to work on a tool for merging duplicated topics (Redirect duplicated topics #7)