refactor: migrate to Rust 2024 edition

[ClementTsang]

Description

A description of the change, what it does, and why it was made. If relevant (such as any change that modifies the UI), please provide screenshots of the changes:

This PR migrates us to Rust 2024 edition. ~~Not too much change needed, thankfully! Most of it is formatting changes, with a tiny bit of actual refactoring.~~ All code/style changes done in https://github.com/ClementTsang/bottom/pull/1681, this PR will just now mostly be us changing version values.

Issue

If applicable, what issue does this address?

Closes: #

Testing

If relevant, please state how this was tested. All changes must be tested to work:

If this is a code change, please also indicate which platforms were tested:

• [ ] Windows
• [ ] macOS
• [ ] Linux

Checklist

If relevant, ensure the following have been met:

• [ ] Areas your change affects have been linted using rustfmt (cargo fmt)
• [ ] The change has been tested and doesn't appear to cause any unintended breakage
• [ ] Documentation has been added/updated if needed (README.md, help menu, doc pages, etc.)
• [ ] The pull request passes the provided CI pipeline
• [ ] There are no merge conflicts
• [ ] If relevant, new tests were added (don't worry too much about coverage)

[codecov[bot]]

Codecov Report

:x: Patch coverage is 75.00000% with 1 line in your changes missing coverage. Please review. :white_check_mark: Project coverage is 43.45%. Comparing base (3d22177) to head (c8c82ca).

Files with missing lines	Patch %	Lines
src/canvas/widgets/network_graph.rs	0.00%	1 Missing :warning:

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1678      +/-   ##
==========================================
- Coverage   44.11%   43.45%   -0.67%     
==========================================
  Files         105      115      +10     
  Lines       15924    16307     +383     
==========================================
+ Hits         7025     7086      +61     
- Misses       8899     9221     +322     

Flag	Coverage Δ
macos-14	37.30% <50.00%> (?)
ubuntu-latest	45.04% <75.00%> (+0.02%)	:arrow_up:
windows-2022	37.64% <50.00%> (+<0.01%)	:arrow_up:

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[ClementTsang]

Might merge this only after doing a stable release.