feat(codex): allow network access in workspace sandbox

Enable sandbox_workspace_write.network_access so MCPorter calls such as
Context7 run without an approval round trip.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

adapters/codex/config/config.toml

@@ -2,6 +2,9 @@ approval_policy = "on-request"
 approvals_reviewer = "auto_review"
 sandbox_mode = "workspace-write"
 
+[sandbox_workspace_write]
+network_access = true
+
 [windows]
 sandbox = "unelevated"