qol-arch-channels

qol-arch-channels

Four channels, pick one. Don't invent a fifth.

Channel	Direction	Use for	Wire
Pull	plugin -> host	Plugin asks now	RuntimeRequest::GetState
Subscribe	plugin -> host (stream)	Plugin reacts to host changes	RuntimeRequest::Subscribe { events } + new RuntimeEvent variant
Action	host -> plugin	Host tells plugin to do something	DaemonRequest { action }
Capability	static	Per-OS feature gate	qol_platform::PlatformCapabilities

Rules

• Event variants are past-tense VerbNoun: FocusChanged, MonitorsChanged, LauncherAppsSynced.
• Payloads are additive only. Breaking shape = new variant, never rename.
• Use #[serde(default)] on new fields so old subscribers still parse.

Anti-patterns

• Manifest subscribes field. Two sources of truth, breaks forward-compat.
• event:<topic> on DaemonRequest. Conflates broadcast with request/response.
• Dynamic capability negotiation. PlatformCapabilities already covers it.