no_std Support for bevy_input_focus

[bushrat011899]

Objective

• Contributes to Tracking Issue: MVP no_std Bevy #15460

Solution

• Switched tracing for log for the atomically challenged platforms
• Setup feature flags as required
• Added to compile-check-no-std CI task

Testing

• CI

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Notes

• Very easy one this time. Most of the changes here are just feature definitions and documentation within the Cargo.toml

[TimJentzsch]

Are there any negative effects when part of the crates use tracing and others log, e.g. harder to configure the log messages?

If yes, perhaps we can make it feature dependent in some way. Wouldnt have to happen in this PR though.

[bushrat011899]

Are there any negative effects when part of the crates use tracing and others log, e.g. harder to configure the log messages?

It should be quite seamless. Tokio provides tracing-log as an official integration for log with tracing that'll capture everything with very little setup (Bevy includes this by default in bevy_log already too). The main thing we miss out on is the span functionality that tracing provides. However, if you're only using the logging macros like tracing::info, they should be identical to log::info, etc.