Fix: add pnpm/action-setup before setup-node in Native and Pinocchio workflows

packageManager field in package.json causes setup-node to look for pnpm
before it is installed, failing with "Unable to locate executable file: pnpm".

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: mikemaccana

.github/workflows/solana-native.yml

@@ -108,6 +108,7 @@ jobs:
       failed_projects: ${{ steps.set-failed.outputs.failed_projects }}
     steps:
       - uses: actions/checkout@v5
+      - uses: pnpm/action-setup@v4
       - name: Use Node.js
         uses: actions/setup-node@v5
         with:
@@ -193,8 +194,7 @@ jobs:
           # Make the script executable
           chmod +x build_and_test.sh
 
-          # Install pnpm
-          npm install --global pnpm
+          # pnpm is already installed via pnpm/action-setup
       - name: Setup Solana Stable
         uses: heyAyushh/setup-solana@v5.9
         with:

.github/workflows/solana-pinocchio.yml

@@ -108,6 +108,7 @@ jobs:
       failed_projects: ${{ steps.set-failed.outputs.failed_projects }}
     steps:
       - uses: actions/checkout@v5
+      - uses: pnpm/action-setup@v4
       - name: Use Node.js
         uses: actions/setup-node@v5
         with:
@@ -193,8 +194,7 @@ jobs:
           # Make the script executable
           chmod +x build_and_test.sh
 
-          # Install pnpm
-          npm install --global pnpm
+          # pnpm is already installed via pnpm/action-setup
       - name: Setup Solana Stable
         uses: heyAyushh/setup-solana@v5.9
         with: