Improvements to docs, blueprints and search

[anna-geller]

Issue description

Problem

For both blueprints + docs repo, keeping develop + main/latest-stable is a bit tedious, and it is hard to keep them in sync.

The api is also affected.

We had merge conflicts between develop and the main branches.

Unclear to which one new people in the company needs to commit things.

E.g. if someone wants to make a change to a blueprint, they need to merge it to both develop and latest-stable.

Next steps

• Single main branch for both repos → latest-stable will be renamed to main on the blueprints repo and develop branch will be killed.
• develop branch will also be killed on the api repo
• When we push to main branch, it will push docs and blueprint changes to kestra develop (snapshot) and to latest stable version of kestra
• we need to add a tag when we release on blueprints, api and docs repos → tag: v0.21.x - TODO needs to add a GitHub action to automate the process
• indexing will be triggered anytime we add a tag on the blueprints and docs repos, but not on api repo → this will allow us to even fix indexing on older versions, we need to delete the version tag, cherry-pick the fix and re-add the the tag
• document internally e.g. in Notion how the process works e.g. if we need to trigger indexing, document which flow in cloud needs to be triggered etc
• search on the main website docs
  • is too strict when typing more than one word; it would be better if we could have a fuzzy search allowing to match broad search terms
  • should index flow definition from blueprint

[brian-mulier-p]

Everything is tackled except the auto tagging CI. I created a follow-up issue here.