[zainrizvi0611-cmd]

Summary

Fixes two runtime issues when using agentops with newer opentelemetry-exporter-otlp-proto-http (>= 1.39 / 1.45+) and short-lived scripts:

1. OpenTelemetry OTLPSpanExporter attribute layout (agentops/sdk/exporters.py):
   • Newer releases of opentelemetry-exporter-otlp-proto-http store headers on self._client._headers and the requests.Session on self._client._transport._session instead of self._headers / self._session.
   • AuthenticatedOTLPExporter now falls back to self._client._headers and self._client._transport._session and propagates updated JWT headers cleanly.
2. Prevent 401 race condition during upload_logfile on short-lived scripts (agentops/client/client.py, agentops/logging/instrument_logging.py):
   • When a short script exits immediately after agentops.init(), the atexit span shutdown could invoke InternalSpanProcessor.on_end -> upload_logfile() before the background authentication thread finished setting client.api.v4.auth_token, resulting in [agentops.InternalSpanProcessor] Error uploading logfile: Upload failed: 401.
   • Added Client.wait_for_auth() synchronization so the JWT token is awaited before span export and logfile upload.