Handle Before errors with OnUsageError

[cyphercodes]

What type of PR is this?

• bug

What this PR does / why we need it:

• Calls OnUsageError when a Before hook returns an error, matching the existing usage-error path and allowing applications to customize the returned error/output.
• Preserves the existing fallback behavior when no OnUsageError handler is configured.
• Adds a regression test for app-level Before errors and updates the operation-order expectations.

Which issue(s) this PR fixes:

Fixes #707

Special notes for your reviewer:

This is intentionally limited to the Before error path discussed in the issue.

Testing

• go test ./...
• go vet ./...
• git diff --check

Release Notes

`Before` hook errors now invoke `OnUsageError` when configured.