fastschema - Unauthenticated NULL Pointer Dereference DoS in Account Recovery Endpoint

A NULL pointer dereference vulnerability in fastschema through v0.15.1 allows an unauthenticated remote attacker to crash the server process with a single HTTP request. The sendOTPEmail function in pkg/auth/local.go dereferences a pointer obtained from an unchecked error path without validating it is non-nil, causing a fatal panic that terminates the entire server when a recovery request is sent to the /api/auth/local/recover endpoint.