reorginise

crates/common/src/service.rs

@@ -0,0 +1,16 @@
+use std::any::Any;
+use std::sync::Arc;
+
+/// Opaque route key identifying a service subscription. Services name their
+/// own keys, so `common` never enumerates them and adding a service never
+/// edits this crate.
+#[derive(Clone, Copy, PartialEq, Eq, Hash, Debug)]
+pub struct Service(pub &'static str);
+
+/// A service event: the route key plus an erased typed payload. The app reads
+/// `key` for fan-out; the consuming module downcasts `payload`.
+#[derive(Clone, Debug)]
+pub struct ServiceEvent {
+    pub key: Service,
+    pub payload: Arc<dyn Any + Send + Sync>,
+}