IBX-11959: Added password requirements info to Set new password screen

[tischsoic]

🎫 Issue	IBX-11959

Related PRs:

• IBX-11959: Exposed configured password requirements to the frontend user#132

Description:

Frontend of the "Set new password" screen. The configured password requirements are listed above the password fields from the data exposed by ibexa/user#132 (ibexa_password_requirements(content_type)), and after a failed submit the requirements that passed are marked with a green check while the backend's own validation messages render under the failing field. No live validation — the state is recomputed server-side on each submit.

All user-facing strings come from backend translations; the only new key is the intro sentence.

Two spacing rules in _login.scss apply to every account screen (login, forgot password, …), both to match the design: a tighter headline line-height and a smaller top margin on form-error rows.

On a passwords-mismatch submit the requirement list stays unmarked: the password constraint doesn't run while the repeated field is out of sync, so met/unmet is genuinely unknown (the design's "all green + passwords don't match" state isn't reachable server-side).

Without ibexa/user#132 the screen renders exactly as before, so this can be reviewed independently.

For QA:

1. Request a reset via Forgot password and open the link from the email.
2. The rules enabled in the User content type's password validators are listed under the heading.
3. Submit abc in both fields — one error per unmet rule under New password, met rules get a green check.
4. Submit two different valid passwords — "Passwords do not match." under Confirm password, list unmarked.
5. Submit a valid password — the reset completes as before.

Documentation:

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

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