Module trace_ui 

Module: Request Lifecycle Tracer TUI Panel

Responsibility

Provides a Ratatui panel that renders the full lifecycle of a single request as a Gantt-chart timeline. Activated with the t key in the TUI; the user types a request_id to trace, and each pipeline stage is rendered as a colour-coded bar proportional to time spent.

Guarantees

• No panics in any rendering or state-update path
• All arithmetic is saturating / checked; no integer overflow
• Zero allocations in the hot render path (only on stage record insertion)

Feature Gate

This module is compiled unconditionally but TracePanel only renders content when the tui feature is active (the binary wires it in).

Structs

RequestTrace

Complete lifecycle record for one request.

StageRecord

Timing record for one pipeline stage within a single request.

TracePanel

State for the request-lifecycle tracer TUI panel.

TraceStore

Thread-safe store of recent request traces.

Enums

TracePanelMode

Interaction mode for the trace panel.

Constants

LIFECYCLE_STAGES

Ordered pipeline stage labels.