Event: EventName
  ↓ (contains: relevant fields)
Class.method() [file:line]
  ↓ (what it does)
Class.method() [file:line] ← 💥 Error here
  ↓
Result: What happens

Problem: Email validation failing

Event: user.email.updated
  ↓ (email: "invalid@")
UpdateUserEmailHandler.execute() [line 281]
  ↓ (validates email format)
EmailValidator.parse() [line 289] ← 💥 Throws ValidationError
  ↓
Result: Error response

Current: Throws
Should: Use safeParse(), return validation error