docs(third-party): separate providers and template docs

[bearomorphism]

Documentation Changes

• Run poetry doc locally to ensure the documentation pages renders correctly
• Check and fix any broken links (internal or external) in the documentation

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 98.68%. Comparing base (120d514) to head (e11ebbc).
⚠️ Report is 848 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1664      +/-   ##
==========================================
+ Coverage   97.33%   98.68%   +1.34%     
==========================================
  Files          42       60      +18     
  Lines        2104     2656     +552     
==========================================
+ Hits         2048     2621     +573     
+ Misses         56       35      -21     

Flag	Coverage Δ
unittests	98.68% <ø> (+1.34%)	⬆️

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[woile]

Can we call them differently? I don't think they are "templates", and templates already fill another roll.
What about "conventions", "rules", or something else?

[bearomorphism]

I'd prefer calling them "rules" or "plugins" to distinguish them from changelog templates.

These third party projects contain data about commit validation rules, commit generation process, bump rules, etc. I agree the name "template" is a bit misleading.

We can add a historical note to point out that such things are called "templates" before this PR.

[bearomorphism]

commitizen/docs/config.md

Line 10 in d037977

Name of the committing rules to use.

In this page, it is also called "rules"

[woile]

If we want to be specific, I think the best would be to start calling them: "conventions".

Teams, people or organizations develop "commit convetions", I don't think "rules", nor "templates" are adequate.
At least, that's what makes sense to me. I would search for "conventions", not "templates".
And yes, they are installed as "plugins" [0]

Keep in mind, that this split, doesn't take into account the fact that you can publish a "convention", a "provider", a "changelog_format" and a "scheme" all under the same package. commitizen itself is an example of this [1]

Maybe it would make more sense to have:
"Third party plugins"
And for each plugging, we document what do they provide:

• a convention
• a scheme
• a provider
• a changelog_format

or all of them

[bearomorphism]

Sounds good.

[bearomorphism]

And for each plugging, we document what do they provide:

For this part, I added some TODOs and we can have future contributors to address the missing content issue. (I would not like to look into what features the plugin provides for each plugin. If I do so, there will be likely inaccurate information which is worse than missing content, and it is also hard for reviewers to spot the misinformation in this PR)

Now this PR is ready for review.