feat: adds hover hint to ".." in record pattern
Hovering on the "rest" pattern in struct destructuring,
```rust
struct Baz {
a: u32,
b: u32,
c: u32,
d: u32
}
let Baz { a, b, ..$0} = Baz { a: 1, b: 2, c: 3, d: 4 };
```
shows:
```
.., c: u32, d: u32
```
Currently only works with struct patterns.
6918009fea
