Feature request: Unwrap tuple

Sometimes, during refactoring, you can end up with assignments like

let (foo, bar) = (expr_a, expr_b);

It would be nice if rust-analyzer had an assist to turn this into

let foo = expr_a;
let bar = expr_b;

The same could also be helpful for

let StructStruct { a, b } = StructStruct { a: expr_a, b: expr_b };

or

let TupleStruct(a, b) = TupleStruct(expr_a, expr_b);

though I haven't seen one of those in the real world yet.

Start by locating rust-analyzer's existing assists for destructuring or refactoring and their tests. Implement support for tuple assignments first, then assess whether struct and tuple-struct patterns fit the same behavior. Done means the requested assignment is split into separate bindings and the assist is covered by tests.