fix: correct WIT binding module structure for user service component

Update BUILD.bazel package_name from "user:service" to "example:user-service"
to match the WIT file definition. Update Rust imports to use the correct
binding path: example::user_service::user_service instead of user::service::user_service.

This resolves WIT binding generation mismatches that were causing compilation
failures in multi-component system examples.

Author: avrabe

examples/cpp_component/multi_component_system/BUILD.bazel

@@ -22,7 +22,7 @@ wit_library(
 
 wit_library(
     name = "user_service_wit",
-    package_name = "user:service",
+    package_name = "example:user-service",
     srcs = ["wit/user_service.wit"],
     world = "user-service",
 )

examples/cpp_component/multi_component_system/components/user_service.rs

@@ -3,10 +3,10 @@ use std::collections::HashMap;
 use uuid::Uuid;
 
 // Use the generated bindings from rust_wasm_component_bindgen
-use user_service_bindings::exports::user::service::user_service::Guest;
+use user_service_bindings::exports::example::user_service::user_service::Guest;
 
 // Re-export the generated WIT types
-pub use user_service_bindings::exports::user::service::user_service::*;
+pub use user_service_bindings::exports::example::user_service::user_service::*;
 
 /// Rust User Service Component
 ///