Enable unreachable_pub lint in xtask

[56steve]

What

Enables the rust.unreachable_pub lint for the xtask crate:

• Removes xtask from the unreachable_pub exclusion list in scripts/sync.sh.
• Adds rust.unreachable_pub = "warn" to crates/xtask/Cargo.toml (matching the ordering sync.sh generates).
• Restricts binary-internal items to pub(crate) across footprint.rs, opentitan.rs, and textreview.rs.

Why

Continues the incremental work of #565 ("Fix all lints currently disabled in scripts/sync.sh"), following #1139 which enabled the same lint for the interpreter. xtask is a host binary, so none of these items were ever reachable outside the crate.

Verification

Ran on host (aarch64-apple-darwin):

• cargo check — clean, 0 warnings
• cargo clippy — clean
• cargo fmt --check — clean

Note: the full Linux CI suite (scripts/ci.sh) was not run locally.

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[gemini-code-assist]

Code Review

This pull request enables the rust.unreachable_pub lint for the xtask crate by removing it from the exclusion list in scripts/sync.sh and adding the lint configuration to crates/xtask/Cargo.toml. Consequently, public visibility modifiers (pub) have been restricted to crate-level visibility (pub(crate)) for various functions and constants across crates/xtask/src/footprint.rs, crates/xtask/src/opentitan.rs, and crates/xtask/src/textreview.rs. There are no review comments, so I have no feedback to provide.

[56steve]

@googlebot I signed it!

[56steve]

@googlebot I signed it!

[56steve]

Hi @ia0, hope you had a good vacation, and thanks for the review!

Quick heads up: the earlier sync failure was just the rustup submodule drift, not anything in this change. I've rebased onto the latest main (past #1144, which bumped rustup to 1.29.1), so that's sorted now. The lints regeneration produced no diff, which confirms the Cargo.toml edit matches what sync.sh generates.

It looks like the fork PR is waiting on a maintainer to approve the workflow run before CI can go again. Whenever you get a chance to kick it off, it should be green. Thanks!

[ia0]

/gemini review

[gemini-code-assist]

Code Review

This pull request enables the rust.unreachable_pub lint for the xtask crate by updating crates/xtask/Cargo.toml and removing xtask from the exclusion list in scripts/sync.sh. As a result, several public functions and constants in footprint.rs, opentitan.rs, and textreview.rs have had their visibility restricted to pub(crate). There are no review comments, and I have no feedback to provide.