ci: pin pnpm to v10 to match Node 20 runtime

pnpm/action-setup@v4 with `version: latest` resolved to pnpm 11,
which requires Node >= 22.13 and broke the build on Node 20.
Pinning to pnpm 10 (matches torus-ts) keeps us on Node 20.

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

Author: PsicoThePato

.github/workflows/deploy.yml

@@ -26,7 +26,7 @@ jobs:
       - name: Setup PNPM
         uses: pnpm/action-setup@v4
         with:
-          version: latest
+          version: 10
           package_json_file: ./package.json
 
       - name: Setup Node

.github/workflows/dry-run-build.yml

@@ -20,7 +20,7 @@ jobs:
       - name: Setup PNPM
         uses: pnpm/action-setup@v4
         with:
-          version: latest
+          version: 10
           package_json_file: ./package.json
 
       - name: Setup Node