72f46a885b
Lands four of the U3 frontend surfaces. Splits T5 because the dispatch covering everything in one shot crashed the runtime mid-execution; this is the salvageable half. - /settings gains three cards alongside Appearance: Profile (display name + email), Password (current + new + confirm with client-side mismatch check), API Token (display + copy + regenerate-with-double-click-confirm). Server error codes map to clear toasts. - /forgot-password — public; takes an email and always shows the success message regardless of whether the email is on file (mirrors the server's no-enumeration posture). - Login page gets a "Forgot password?" link below the existing register link. - API client functions for the four /me endpoints (changePassword, updateProfile, getAPIToken, regenerateAPIToken), the SMTP admin trio (getSMTPConfig, updateSMTPConfig, testSMTPConfig), and the forgot/reset auth pair (forgotPassword, resetPassword). Tests for these surfaces + /reset-password page + admin SMTP card land in T5b (next follow-up).