Enable Vercel Git deploys for main only.

Disable staging branch deployments in vercel.json and drop the redundant GitHub Actions Vercel deploy step to avoid double production builds.

.github/workflows/deploy.yml

@@ -49,15 +49,3 @@ jobs:
         env:
           SUPABASE_ACCESS_TOKEN: ${{ secrets.SUPABASE_ACCESS_TOKEN }}
         run: supabase db push --linked --include-seed
-
-      # Sole production deploy path. vercel.json ignoreCommand skips Git-triggered
-      # Vercel builds so pushes do not produce a duplicate deployment.
-      - name: Set up Vercel CLI
-        run: npm install --global vercel@54.4.1
-
-      - name: Deploy to Vercel production
-        env:
-          VERCEL_TOKEN: ${{ secrets.VERCEL_TOKEN }}
-          VERCEL_ORG_ID: ${{ secrets.VERCEL_ORG_ID }}
-          VERCEL_PROJECT_ID: ${{ secrets.VERCEL_PROJECT_ID }}
-        run: vercel deploy --prod --yes --token "$VERCEL_TOKEN"

vercel.json

@@ -2,9 +2,7 @@
   "$schema": "https://openapi.vercel.sh/vercel.json",
   "git": {
     "deploymentEnabled": {
-      "main": false,
       "staging": false
     }
-  },
-  "ignoreCommand": "echo 'Git integration builds disabled; production deploys via GitHub Actions on main only.' && exit 0"
+  }
 }