Module observer 

Phase 1 of #221: the process-observation capability model and the portable process-lifecycle baseline.

This module defines the stable observation types — ObserverConfig, ObserverCapabilities, ObserverEvent, and the ObserverSubscriber handle — plus the always-available lifecycle backend that emits started and exited events for child processes spawned by this crate.

Scope (Phase 1 only)

Only the EventCategory::Lifecycle category is supported. Every other category (File, Network, Process) reports unavailable with an honest reason, because syscall-level backends (seccomp/eBPF/ETW) are Phase 3 work and are deliberately not wired here.

Off by default

Observation is entirely opt-in. A NativeProcess emits no events unless an ObserverConfig is attached via NativeProcess::with_observer (or the equivalent builder seam). With no observer configured the lifecycle hooks are inert: no channel, no allocation, no events.

The handle is a plain std::sync::mpsc receiver so the lifecycle baseline stays free of the daemon runtime (tokio/IPC). Phase 2 layers the daemon-owned subscriber model on top of these same event types.

Structs

CategoryCapability

Capability report for one EventCategory: the negotiated support level, the backend that would serve it, and a human-readable reason.

ObserverCapabilities

The full capability matrix produced by ObserverCapabilities::negotiate.

ObserverConfig

Opt-in configuration that turns process observation on for a single NativeProcess.

ObserverEvent

A single observation emitted by the lifecycle baseline.

ObserverSubscriber

Receiver handle for observation events.

Enums

CapabilitySupport

Negotiated support level for a single EventCategory.

EventCategory

Category of observable process activity.

ObserverEventKind

What happened to an observed process.