KCL: Support non-ASCII identifiers (#7525)

Both human and LLMs want to write KCL code in non-English languages. This is important and we should support it.

Note that errors are currently a bit broken with non-ASCII identifiers, see #4327

rust/kcl-lib/src/simulation_tests.rs

@@ -3605,3 +3605,24 @@ mod user_reported_union_2_bug {
         super::execute(TEST_NAME, false).await
     }
 }
+mod non_english_identifiers {
+    const TEST_NAME: &str = "non_english_identifiers";
+
+    /// Test parsing KCL.
+    #[test]
+    fn parse() {
+        super::parse(TEST_NAME)
+    }
+
+    /// Test that parsing and unparsing KCL produces the original KCL input.
+    #[tokio::test(flavor = "multi_thread")]
+    async fn unparse() {
+        super::unparse(TEST_NAME).await
+    }
+
+    /// Test that KCL is executed correctly.
+    #[tokio::test(flavor = "multi_thread")]
+    async fn kcl_test_execute() {
+        super::execute(TEST_NAME, true).await
+    }
+}