wip(inventory-agent): local presence advertisement and discovery using mdns almost working

harmony_inventory_agent/src/local_presence/mod.rs

@@ -0,0 +1,16 @@
+mod discover;
+pub use discover::*;
+mod advertise;
+pub use advertise::*;
+
+pub const SERVICE_NAME: &str = "_harmony._tcp.local.";
+const VERSION: &str = env!("CARGO_PKG_VERSION");
+
+// A specific error type for our module enhances clarity and usability.
+#[derive(thiserror::Error, Debug)]
+pub enum PresenceError {
+    #[error("Failed to create mDNS daemon")]
+    DaemonCreationFailed(#[from] mdns_sd::Error),
+    #[error("The shutdown signal has already been sent")]
+    ShutdownFailed,
+}