Autofill security improvements

[dbro]

Autofill

• Harden same-profile autofill authorization and destination validation.
• Validate destination URL and clicked field before filling sensitive values.
• Improve autofill popup focus behavior after fills and errors.
• Show clearer error states for invalid password / one-time-code destination fields.
• Count autofill popup uses and keep the popup open for repeated single-field insertions.
• Add visual inserted-field checkmarks after successful single-field insertion.
• Support named custom fields in autofill sequences, compatible with official Password Safe code
• Improve incognito / cross-profile pairing messaging.

Vault Settings

• Add per-writable-vault master password rotation.
• Allow changing unlock difficulty rounds when changing the master password.
• Surface vault format and unlock difficulty under a shared SECURITY section for primary and secondary vaults.
• Preserve secondary vault auto-unlock credentials when rotating the primary vault password.
• Clear biometric enrollment after primary vault password rotation.
• Add profile reset action to clear all Portpass configuration settings.
• Align AUTOFILL section row sizing/spacing with VAULTS section styling.