feat: add milestone 6 CLI polish

Add shell completion generation, improve first-run device messaging,
and include HTTP endpoint details in daemon startup output.

src/daemon/registry.rs

@@ -179,19 +179,11 @@ impl Default for DeviceRegistry {
 }
 
 /// A registry of platform adapters available to the daemon.
-#[derive(Debug, Clone)]
+#[derive(Debug, Clone, Default)]
 pub struct AdapterRegistry {
     roku: RokuAdapter,
 }
 
-impl Default for AdapterRegistry {
-    fn default() -> Self {
-        Self {
-            roku: RokuAdapter::new(),
-        }
-    }
-}
-
 impl AdapterRegistry {
     /// Build the adapter registry from the loaded daemon config.
     pub fn from_config(config: &TvctlConfig) -> Self {