fix: add winapi/winreg dependencies to services crate for Windows

machine_id_service.rs uses winreg and winapi for Windows registry
access but these were only declared in the main package, not in
the proxycast-services crate where the code now lives.

src-tauri/Cargo.lock

@@ -7007,6 +7007,8 @@ dependencies = [
  "uuid",
  "voice-core",
  "whoami",
+ "winapi",
+ "winreg 0.52.0",
  "zip",
 ]
 

src-tauri/crates/services/Cargo.toml

@@ -64,3 +64,7 @@ rusqlite.workspace = true
 [dev-dependencies]
 tempfile.workspace = true
 proptest.workspace = true
+
+[target.'cfg(windows)'.dependencies]
+winapi.workspace = true
+winreg.workspace = true