CI proof-surface failures on PR 671 after FOD refresh

PR: https://github.com/overengineeringstudio/effect-utils/pull/671
Run: https://github.com/overengineeringstudio/effect-utils/actions/runs/26329049439

After refreshing the stale pnpm-deps fixed-output hashes, the package/lint/typecheck/FOD surfaces are mostly green, but CI remains blocked by proof-surface failures unrelated to the notion-md batch-sync code.

Observed symptoms:

• Nix/devenv setup intermittently fails fetching public GitHub tarballs with HTTP 401, e.g. nix-community/nixd and pietdevries94/playwright-web-flake.
• Several rerun jobs were cancelled during setup/proof steps.
• test-integration-notion also hit a timeout in NotionSearch (integration) > searchStream > streams with filter; this appears outside the notion-md batch-sync path but should be checked for flakiness.

Local proof completed on the PR branch:

• dt check:quick --no-tui passed.
• nix build .#genie-pnpm-deps .#megarepo-pnpm-deps .#notion-cli-pnpm-deps .#notion-md-pnpm-deps .#tui-stories-pnpm-deps --print-build-logs passed after hash refresh.

This issue is for CI/proof-surface follow-up, not for secrets or private repo context.

Start with PR 671 and the linked Actions run, then inspect the Nix/devenv setup and proof jobs that fetch the named GitHub tarballs. Check the test-integration-notion searchStream timeout separately; done means the affected CI/proof surfaces complete reliably and the reported integration test behavior is accounted for.