Show All Auth Webhook Methods Checked When No Specific Method is Selected

[chacha912]

Description:

There is an inconsistency between the UI state and actual behavior of Auth Webhook method selection.

When no Auth Webhook methods are explicitly selected, the webhook URL is called for ALL methods
When all Auth Webhook methods are deselected, the webhook URL is still called for ALL methods
However, the UI does not reflect this behavior, showing methods as unchecked even though they are effectively active

The UI should accurately reflect the actual webhook behavior:

1. When setting a webhook URL:

   • All method checkboxes should be automatically checked
   • This reflects that the webhook is active for all methods by default

2. When deselecting all webhook methods:

   • All method checkboxes should remain checked
   • This reflects that deselecting all methods defaults to checking all methods

Why: Fix UI Inconsistency

[chacha912]

I'd like to discuss the current webhook method behavior.
Currently, webhooks trigger for all methods when none are specified, and users have to delete the URL to stop this behavior. This feels a bit unintuitive and could lead to confusion.
What do you think about modifying the Yorkie server behavior so that webhooks do not trigger at all when methods are not specifically set? This would make the behavior more explicit and give users better control over when webhooks are triggered.
Let me know your thoughts!