chore: replace fxhash crate with rustc-hash

[Saschl]

Fixes #10405

Summary of Changes

1:1 replacement of fxhash with rustc-hash

Screenshots (if necessary)

References

Additional context

Discord username (if different from GitHub):

Testing instructions

For both A32NX/A380X

1. Load the plane and ensure the systems work as expected (HYD/ELECT/Flight controls etc.)
2. Takeoff and ensure the systems work as expected (HYD/ELECT/Flight controls etc.)

How to download the PR for QA

Every new commit to this PR will cause new A32NX and A380X artifacts to be created, built, and uploaded.

1. Make sure you are signed in to GitHub
2. Click on the Checks tab on the PR
3. On the left side, find and click on the PR Build tab
4. Click on either flybywire-aircraft-a320-neo, flybywire-aircraft-a380-842 (4K) or flybywire-aircraft-a380-842 (8K) download link at the bottom of the page

[Gurgel100]

LGTM. Only the linting remain to be fixed.

[Jonny23787]

Quality Assurance Tester Report

Discord Username : jonny_23
Object of testing : #10412
Aircraft : A32NX/A380X
Simulator : 2020
Tier of Testing : 1
Date : 04/12/2025

Testing Process:

1. Tested both aircraft, confirmed systems worked as expected.

Testing Results:
Passed