Improve search UI/UX

[EmmanuelMess]

As part of the effort to make breathe/exhale comparable to Doxygen, I would recommend improving the UI/UX of the search interface.

For a simple comparison see:

From http://docs.ros.org/en/jazzy/p/rclcpp/search.html?q=transform&check_keywords=yes&area=default

And compare to:

From https://docs.ros2.org/foxy/api/rclcpp/index.html

I would recommend:

1. Automatically search in place (without navigating to a new page)
2. Show only relevant snippets, in our case it would be python files, cpp files and some docs
3. Better management of space
4. Better sorting and grouping of entries into classes files and docs

[tfoote]

Automatically search in place (without navigating to a new page)

This sounds like a good enhancement ticket for exhale or sphinx more than for rosdoc2. We don't implement the search UI, so things like the instance floating responses are not something that we're likely to work on.

Show only relevant snippets, in our case it would be python files, cpp files and some docs

Are there search responses that you consider irrelevant in the search results?

When I search the equivalent to your doxygen query I see generally pretty good coverage and relevancy: https://docs.ros.org/en/jazzy/p/rclcpp/search.html?q=create_publisher&check_keywords=yes&area=default#

Better management of space
Better sorting and grouping of entries into classes files and docs

These are generally pretty subjective. If there are settings for our instance that we can tweak, maybe layouts for the better spacing etc. We can look at that. And if there's ways to provide more information to the search for ranking that would be great. To make an improvement to the tool we'll need an understanding of what's better or worse versus necessarily personal preference. We generally follow what are best practices and use the defaults which are maintained and optimized by others. And to diverge from the best practices for these tools we'll want to have a pretty compelling case.