next.js

c8f9fcb5 - [15.5.x][ci] Port sccache fallback from #91873/#92911/#93164/#94319 (#94848)

[15.5.x][ci] Port sccache fallback from #91873/#92911/#93164/#94319 (#94848) ### Why? Stacked replacement for #94844. This is the top PR in the `next-15-5` backport stack and is based on #94847. This was discovered while investigating the fork PR CI failure on #94829. Fork PRs to `next-15-5` do not receive `secrets.TURBO_TOKEN`, but the pinned `ijjk/rust-cache` action throws when `TURBO_TOKEN` is missing. Canary no longer uses that action for these Rust cache paths; it starts the local `sccache` action and only configures Vercel Artifacts when a token is available. This ports the fork-safe cache behavior from canary without taking the broader native-builder and workflow rewrites from the source PRs. Source PRs / ported parts: - #91873: add the local `.github/actions/sccache` action and move Rust workflows off `ijjk/rust-cache`. - #92911: install `cargo-binstall` and use the `vercel/sccache` cargo-binstall path. - #93164: keep the Vercel Artifacts token/team wiring used by canary. - #94319: remove the remaining `build_and_deploy.yml` `ijjk/rust-cache` step. ### How? - Add the canary `.github/actions/sccache` action and install `cargo-binstall` from `setup-rust`. - Replace the remaining `ijjk/rust-cache` usage in reusable Rust workflows with the local `sccache` action. - Remove the remaining `build_and_deploy.yml` rust-cache step so fork PRs do not load the token-requiring external action. <!-- NEXT_JS_LLM_PR -->