Move each plugin index page from Markdown to model-based doc

[brian-mulier-p]

Issue description

Currently the index of each plugin where for a given plugin we list every tasks / triggers / ... it includes (here) is a bit ugly. The goal is to move from an API-generated markdown page to a model-based generation. Basically the front-end will instead fetch the model data and will generate the page.

It will allow us to easily modify the content and introduce in an easier manner custom components.

What to do to achieve such result:

• for now, call the /v1/plugins API that will return every tasks of every plugins (a filtered endpoint will be added later)
• filter by name === slug
• cutoff all tasks / triggers / conditions (everything that is a list except aliases that you don't include) by the group property (so for snowflake it's io.kestra.plugin.jdbc.snowflake for eg.)
• split everything by dot
• keep the last word after dot as the task name (so the link one)
• recursively indent with 1 category per word ahead of the task name
• group them if they have similar categories

[anna-geller]

@brian-mulier-p I see everything is checked :) can the issue be closed?

[t-chatoyan]

#1510
kestra-io/ui-libs#37

[brian-mulier-p]

Waiting for a Cloudflare ticket due to building issue