[codex] Fix data table step-up flow

[DavidBabinec]

Summary

• Route data table schema mutations through the shared step-up flow so step_up_required opens the password dialog and retries instead of rendering raw text.
• Swallow the shared step-up cancellation sentinel across table and field schema mutation UI.
• Extract NewFieldDialog model helpers and remove it from the module-size grandfather list.
• Pin ESLint's TypeScript config root and ignore local agent worktrees to avoid .claude root ambiguity during lint.

Verification

• bun run build
• bun run lint
• bun test
• bunx react-doctor@latest --verbose --diff main --blocking warning
• Browser smoke on http://localhost:5178/admin/data with a disposable local stack: verified the step-up dialog appears, raw step_up_required does not render, and password confirmation retries table creation successfully.