Upgrade Rust to 1.84.0

[Zixing Liu]

Upgrade Rust to 1.84.0

Notable changes in 1.84:

* Cargo now considers minimum supported Rust version (MSRV) when resolving dependencies

You can find the release notes here: https://blog.rust-lang.org/2025/01/09/Rust-1.84.0.html

[Zixing Liu (liushuyu-011)]

Preliminary packages have been uploaded to https://launchpad.net/~liushuyu-011/+archive/ubuntu/rust-updates-1.84/+packages.
The complete corresponding source can be found at https://git.launchpad.net/~canonical-foundations/ubuntu/+source/rustc/tree/?h=merge-1.84.

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Lintian report:
Now running lintian rustc-1.84_1.84.0+dfsg0ubuntu1-0ubuntu1_source.changes ...
E: rustc-1.84 source: field-too-long Vendored-Sources-Rust (12278 chars > 5000)
E: rustc-1.84 source: unknown-file-in-debian-source [debian/source/lintian-overrides.in]
E: rustc-1.84 source: version-substvar-for-external-package Depends ${binary:Version} cargo-1.84 -> rustc [debian/control:305]
W: rustc-1.84 source: mismatched-override missing-license-paragraph-in-dep5-copyright debian/copyright mpl-2.0+ (*) [debian/source/lintian-overrides:19]
W: rustc-1.84 source: missing-license-paragraph-in-dep5-copyright mit-0 [debian/copyright:3430]
W: rustc-1.84 source: unknown-field Vendored-Sources-Rust
N: 0 hints overridden; 1 unused override
N: Some overrides were ignored.
N: Use --verbose for more information.
Finished running lintian.
Now signing changes and any dsc files...
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Autopkgtest reports:

https://autopkgtest.ubuntu.com/results/autopkgtest-plucky-liushuyu-011-rust-updates-1.84/?format=plain