highlights(rust): distinguish between "for" in loops and impl_item

Fixes #3641

queries/rust/highlights.scm

@@ -211,13 +211,15 @@
 [
   "break"
   "continue"
-  "for"
   "in"
   "loop"
   "while"
 ] @repeat
 
-
+(impl_item
+  "for" @keyword)
+(for_expression
+  "for" @repeat)
 
 ;;; Operators & Punctuation
 

tests/query/highlights/rust/for.rs

@@ -0,0 +1,15 @@
+struct Foo;
+
+// Issue https://github.com/nvim-treesitter/nvim-treesitter/issues/3641
+// Distinguish between for in loop or impl_item
+impl Drop for Foo {
+    //     ^ @keyword
+   fn drop(&mut self) {}
+}
+
+fn main() {
+    for i in 0..128 {
+    // <- @repeat
+        println!("{i}");
+    }
+}