feat: login failed webhook

[barnarddt]

Add a webhook to fire after a login attempt has failed

Related issue(s)

#3580

Checklist

• I have read the contributing guidelines.
• I have referenced an issue containing the design document if my change
  introduces a new feature.
• I am following the
  contributing code guidelines.
• I have read the security policy.
• I confirm that this pull request does not address a security
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• I have added tests that prove my fix is effective or that my feature
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Further Comments

[aeneasr]

Thank you for the PR! While the implementation demonstrates solid effort, it has limitations: (a) it only addresses login scenarios, and (b) it does not handle all error cases.

We recently added tracing events that include failures, such as "login failed." Using these events to notify external systems would be more suitable than introducing an additional webhook. Webhooks are intended to modify, extend, or alter business logic within a specific flow (e.g., adjusting user data or blocking logins).

Tracing events also enable tracking incomplete logins, providing more comprehensive insights.

Given these considerations, we are unlikely to merge this PR despite the quality of the work. Thank you for your understanding!