BSM Magic Login v1.0.39 — Shared Login JavaScript Guard

- Prevents a JavaScript null-reference error on magic-link confirmation and other shared login-shell screens that do not include the unified identity row.
- Checks required sign-in controls before any DOM mutation; normal unified sign-in behavior remains unchanged.
- Preserves branded confirmation screen, explicit Continue action, passkey enrollment, notice severity styling, and native WordPress login fallback.
- No authentication token validation or session behavior changed.

Install: Plugins > Add New > Upload Plugin > choose ZIP > Replace current version.
