SetupTracing merged resource.Default() (schema 1.43.0 under otel 1.45.0)
with semconv/v1.24.0's schema URL, so resource.Merge errored with
'conflicting Schema URL' and the backend exited at startup whenever an
OTLP endpoint was configured. resource.NewSchemaless keeps service.name
without pinning a schema, surviving otel major bumps.
Keep Next on the patched 15.5 line instead of the Next 16 Dependabot bump, and move OpenTelemetry and gRPC to the versions that close the open Go alerts.
Shared NAT egress makes client IP unusable for uniqueness checks. Gate the
behavior behind REGISTRATION_ENFORCE_IP (default false) for public/invite signup.
ahp