fix: restore packageManager pin; bump deploy actions to v6

Publish failed: pnpm/action-setup needs the packageManager key (dropped during
the pnpm v11 store migration). Match rest-client: pnpm@11.5.2, actions @v6.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: maxholman

.github/workflows/deploy.yml

@@ -13,13 +13,13 @@ jobs:
       id-token: write
       attestations: write
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
-      - uses: pnpm/action-setup@v4
+      - uses: pnpm/action-setup@v6
 
-      - uses: actions/setup-node@v4
+      - uses: actions/setup-node@v6
         with:
-          node-version: 24
+          node-version: 26
           registry-url: https://registry.npmjs.org/
           cache: "pnpm"
 

package.json

@@ -55,5 +55,6 @@
 	},
 	"engines": {
 		"node": ">=26.0.0"
-	}
+	},
+	"packageManager": "pnpm@11.5.2"
 }