fix(ci): publish v2 as next

.github/workflows/publish.yml

@@ -32,6 +32,9 @@ permissions:
   contents: write
   packages: write
 
+env:
+  OPENCODE_CHANNEL: ${{ (github.ref_name == 'v2' && 'next') || '' }}
+
 jobs:
   version:
     runs-on: blacksmith-4vcpu-ubuntu-2404