feat(RustLangDoc): 2.16 support Rust | 支持 Rust

src/test/java/io/github/linwancen/plugin/show/demo/main.rs

@@ -0,0 +1,9 @@
+// file tree doc is any where not doc comment
+
+fn main() {
+    my_fun()
+}
+
+/// rust doc
+/// [`my_fun`]
+fn my_fun() {}