Module context 

Proxy context data structures.

The per-request ProxyContext composes several single-responsibility sub-structs so each cluster of related fields can be reasoned about (and initialised) independently:

• RouteInfo — backend selection + path rewriting (populated in request_filter).
• ConversionFlags — boolean state machine that drives whether and how bodies are converted.
• ConversionBuffers — buffered request/response bodies + stream parse cursor.
• UpstreamDiagnostics — observed upstream status / content-type / chunk count, kept for logging and bypass decisions.
• FollowUpContext — conversation messages we’ll persist after the upstream completes (for previous_response_id expansion).

The root keeps only fields that don’t fit any cluster: start_time, model, and the streaming StreamState.

Structs

ConversionBuffers

Buffered request/response bodies and the stream-parse cursor.

ConversionFlags

Boolean state machine that records what kind of conversion is in flight.

FollowUpContext

Information needed to persist a completed turn for subsequent previous_response_id lookups.

ProxyContext

Proxy context attached to each request session.

RouteInfo

Backend selection and request-path information.

UpstreamDiagnostics

Upstream observations for diagnostics + bypass decisions.