Handle HTTP errors specific to sandbox creation.
Maps API error responses to specific exception types:
- 408: ResourceTimeoutError (sandbox didn't become ready in time)
- 422: ValidationError (bad input) or SandboxCreationError (runtime)
- 429: QuotaExceededError (org limits exceeded)
- 503: SandboxCreationError (no resources available)
- Other: Falls through to generic error handling
