Docs/add keypoint detection

[LinasKo]

Description

• Added mentions to KeyPoints in index.md
• Added an extensive dedicated page for keypoint detection, which should answer most questions users may have.

⚠️ Issues that affect other docs such as markdown formatting of collapsable panes was not tackled. ⚠️ We don't yet have YOLO NAS keypoint models on Universe, so I did not mention it.

Type of change

• [x] This change requires a documentation update

How has this change been tested, please provide a testcase or example of how you tested the change?

I've built the docs with mkdocs build, served with mkdocs serve, visually checked for unclear parts.

It would be good to have some extra eyes on this.

Any specific deployment considerations

Installation of mkdocs dependencies is outdated.

Here's my requirements/requirements.docs.txt file:

mike==1.1.2
mkdocs~=1.5.3
mkdocs-material==9.5.18
mkdocstrings-python
mkdocs-swagger-ui-tag==0.6.3
pillow
cairosvg
mkdocs-gen-files
mkdocs-literate-nav
mkdocs-macros-plugin
mkdocs-jupyter

Docs

• [x] Docs updated? What were the changes:

• first paragraph of index.md

• Mentioned keypoints detection in YOLOv8

• new page under "Run a Model": Run Keypoint Detection

[LinasKo]

I'm seeing a lot of tests failing. How much of this is expected? It seems like git is failing, and docker credentials aren't configured.

Apart from that - ready for review.

[LinasKo]

Added InferencePipeline, tested that it works. Ready for review, assuming tests should be failing.

[grzegorz-roboflow]

@LinasKo , I think the CI might be failing because this PR comes from the fork.