fix(ci): repair macos rustup shims in releases

[rgbkrk]

Summary

• add a reusable release action that reinstalls upstream rustup shims on macOS after Swatinem/rust-cache
• run that repair in the macOS release executable, notebook, and Python wheel jobs
• move macOS target installation after the repair so target setup does not use the broken cached/Homebrew shim

Context

The latest nightly run is still on macos-14-arm64/20260512.0058.1 and fails after cache restore with cargo resolving to rustup-init:

• release / Build macOS Executables: cargo build ... -> Usage: rustup-init[EXE]
• release / Build macOS x64 Notebook: cargo binstall ... -> Usage: rustup-init[EXE]

This matches the upstream runner-images rustup regression tracked in actions/runner-images#14097. The latest published macOS 14 arm64 image is still 20260512.0058.1, so rerunning is still image/cache lottery rather than a durable release unblock.

Verification

• actionlint .github/workflows/release-common.yml
• cargo xtask lint --fix

[pullfrog]

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