Initial MetaCrate rewrite shell

tests/compat/src/lib.rs

@@ -0,0 +1,9 @@
+//! Shared failure marker used by generated compatibility tests.
+
+/// Fails a not-yet-translated upstream test while retaining parity metadata.
+#[track_caller]
+pub fn pending(source: &str, line: u64, test: &str, attribute: &str, body_sha256: &str) -> ! {
+    panic!(
+        "pending LibreMetaverse parity test {test} ({attribute}) from {source}:{line}; C# body sha256={body_sha256}"
+    )
+}