Embassy enable thread and interrupt by default, enable embassy when building docs

[MabezDev]

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Pull Request Details 📖

Description

Closes #1484, it also enables the embassy feature to be build in the docs run.

TODO

• Fix up missing docs from the executor module
• Re write the top level docs
• More testing? Can we add a HIL test to test our interrupt executor (and in the future multi-core thread mode one)?

[bjoernQ]

I like the idea - if we can somehow make something similar for the time-drivers using embassy on ESP32 will become a much, nicer experience!

[bjoernQ]

Will need a change in esp-wifi but for the next HAL release we already need to change a couple of things there ... so just one thing more

[JurajSadel]

LGTM, thanks! There is one discussion thread still open, could we merge this as is?

[jessebraham]

LGTM, thanks for this!

[kaspar030]

Hey everyone!

We're using a custom executor inside a thread. Unfortunately making the use of esp-hal-embassy's executors always included clashes with that even if we don't initialize those executors because __pender() is defined twice.

Could we make inclusion of the executors optional again? I'd suggest a single feature executors that's default. Alternatively, a feature no-executors that's opt-in and would disable all esp-hal-embassy executor code.

[kaspar030]

I'd suggest a single feature executors that's default.

I implemented this in #1683.