Constraint: PasswordStrength

[cursor]

Goal

Add a PasswordStrength constraint — heuristic password strength evaluation inspired by Symfony (Assert\PasswordStrength), without external APIs.

Reference

• Symfony: Symfony\Component\Validator\Constraints\PasswordStrength.
• Align thresholds/levels with the reference as much as possible without copying third-party dictionaries.

Constraints

• No new dependencies — stdlib only (length, character classes, simple heuristics such as repeats/sequences).

Scope

• Explicitly document that this is not zxcvbn and not Have I Been Pwned; tests for weak/sufficient passwords.

Complexity

3 / 5.

---

Migrated from Linear: IGO-37
Priority: Medium
Estimate: 3 points