Update `rand_core` to 0.9

[HaoboGu]

I found that both trouble-host and examples use rand_core = 0.6. Is there any particular reason to not bump version to latest?

[AndWass]

I made a quick attempt but one of the dependencies of p256 is stuck on rand_core 0.6.4 so you need that version to get the correct trait versions.

[lulf]

Yeah, would be great to update it, but I believe the p256 dependency is where I got stuck as well.

[lure23]

Their version 0.14 (unreleased) CHANGELOG lists:

Update to rand_core v0.9 (diff)

So the issue becomes pushing for a crate release, New crate versions?

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...and the actual tracking issue is: Tracking issue for next release series

[finalyards]

For those interested, the pr-rand-catchup branch is now up to the latest versions.

• rand is preparing for 0.10 release; I jumped over 0.9 and preparing for it
• all dependencies are Release Candidate status (no pre)
• there are some API changes where I'd like to have a discussion with people better informed with trouble - but this can also wait until, say, January

🧚‍♀️ Usage of the branch would be welcome, so that we can see if I've messed up something. I only have ESP32 (C3, C6) and nRF54 hardware available.