Refresh dependencies in the Rust server generator

[dsteeley]

Needed to update serde_valid for validation to be compatible with the swagger-rs crate that also uses that dependency.
Have refreshed a few other dependencies whilst in the area.

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Summary by cubic

Refresh Rust server generator dependencies to resolve serde_valid conflicts with swagger-rs and keep the template current. This ensures generated servers compile cleanly with the latest ecosystem crates.

• Dependencies
  • Upgrade serde_valid to 2.0 for compatibility with swagger-rs.
  • Bump hyper to 1.8, hyper-util to 0.1.18, and tokio to 1.49.
  • Update percent-encoding to 2.3.2 and jsonwebtoken to 10.0.0 with rust_crypto.
  • Update Cargo.mustache and regenerate sample Cargo.toml files.

^{Written for commit 86dd147. Summary will update on new commits.}

[cubic-dev-ai]

No issues found across 8 files