[ci] Roll pinned nightly toolchain

[google-pr-creation-bot]

Automated changes by create-pull-request GitHub action

[gemini-code-assist]

Summary of Changes

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This pull request updates the continuous integration configuration to utilize a more recent nightly Rust toolchain. This ensures that automated builds and tests are executed against the latest specified nightly compiler, maintaining compatibility and leveraging recent language features or fixes.

Highlights

• CI Toolchain Update: The pinned nightly Rust toolchain version in Cargo.toml has been updated from nightly-2025-10-16 to nightly-2025-10-17.

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[gemini-code-assist]

Code Review

This pull request automatically updates the pinned nightly toolchain version. However, the date used for the toolchain (nightly-2025-10-17) appears to contain an incorrect year. Since toolchains for future dates are not available, this will likely cause the CI builds to fail. This should be corrected, and the automation that created this PR should be investigated to fix the root cause of the incorrect year.

[gemini-code-assist]

The year 2025 in the nightly toolchain version is incorrect because toolchains for future dates are not available. This will cause CI to fail when it attempts to install this toolchain. The year should be corrected to the current year. The automation that generated this PR may also need to be fixed to prevent this from recurring.

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 88.89%. Comparing base (59a569e) to head (7fda57e).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2736   +/-   ##
=======================================
  Coverage   88.89%   88.89%           
=======================================
  Files          20       20           
  Lines        5423     5423           
=======================================
  Hits         4821     4821           
  Misses        602      602           

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