ci(musl): replace corepack with oxc-project/setup-node (#367)

## Summary

The musl test job runs in a Node Alpine container and used `corepack
enable` to bootstrap pnpm. Node 25 unbundles corepack, so the renovate
bump from `node:22-alpine3.21` to `node:25-alpine3.21` (#361) fails with
`corepack: command not found` (see [run
24967913479](https://github.com/voidzero-dev/vite-task/actions/runs/24967913479/job/73105843537?pr=361)).

Use `oxc-project/setup-node@v1.2.0`, which installs pnpm directly and
gates the pnpm-store cache to `main` (save on main, restore-only on
PRs). Mirrors the existing pattern at `.github/workflows/ci.yml:148-153`
(action + follow-up `pnpm install` for test bins).

🤖 Generated with [Claude Code](https://claude.com/claude-code)

---------

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: Boshen

.github/workflows/ci.yml

@@ -132,25 +132,11 @@ jobs:
       - name: Run tests
         run: ${{ matrix.cargo_cmd }} test --target ${{ matrix.build_target }}
 
-      # For x86_64-apple-darwin on arm64 runner, install x64 node so fspy preload dylib
-      # (compiled for x86_64) can be injected into node processes running under Rosetta.
-      # oxc-project/setup-node doesn't support the architecture input, so use
-      # pnpm/action-setup + actions/setup-node directly.
-      - uses: pnpm/action-setup@fc06bc1257f339d1d5d8b3a19a8cae5388b55320 # v4.4.0
-        if: ${{ matrix.target == 'x86_64-apple-darwin' }}
-
-      - uses: actions/setup-node@48b55a011bda9f5d6aeb4c2d9c7362e8dae4041e # v6.4.0
+      # x86_64-apple-darwin runs on arm64 runner under Rosetta; install x64 Node
+      # so fspy's x86_64 preload dylib can be injected into spawned node procs.
+      - uses: oxc-project/setup-node@ab97f03642370d79a7e96dd286bd02a1be40e0ba # v1.3.0
         with:
-          node-version-file: .node-version
-          architecture: x64
-        if: ${{ matrix.target == 'x86_64-apple-darwin' }}
-
-      - uses: oxc-project/setup-node@4c26e7cb3605b6bdef5450dacd02c434b10fd8ba # v1.2.0
-        if: ${{ matrix.target != 'x86_64-apple-darwin' }}
-
-      # `pnpm install` prepares test bins used in snapshot tests
-      # Must run after setup-node so correct native binaries are installed
-      - run: pnpm install
+          architecture: ${{ matrix.target == 'x86_64-apple-darwin' && 'x64' || '' }}
 
       - name: Run ignored tests
         run: ${{ matrix.cargo_cmd }} test --target ${{ matrix.build_target }} -- --ignored
@@ -201,10 +187,7 @@ jobs:
       - name: Run tests
         run: cargo test
 
-      - name: Install pnpm and Node tools
-        run: |
-          corepack enable
-          pnpm install
+      - uses: oxc-project/setup-node@ab97f03642370d79a7e96dd286bd02a1be40e0ba # v1.3.0
 
       - name: Run ignored tests
         run: cargo test -- --ignored
@@ -225,7 +208,7 @@ jobs:
           tools: cargo-shear@1.11.1,cargo-autoinherit@0.1.6
           components: clippy rust-docs rustfmt
 
-      - uses: oxc-project/setup-node@4c26e7cb3605b6bdef5450dacd02c434b10fd8ba # v1.2.0
+      - uses: oxc-project/setup-node@ab97f03642370d79a7e96dd286bd02a1be40e0ba # v1.3.0
       - run: pnpm oxfmt --check
       - run: cargo autoinherit && git diff --exit-code
       - run: cargo shear --deny-warnings