Fix clippy::redundant_clone lint violations (#36558)

This removes around 900 unnecessary clones, ranging from cloning a few
ints all the way to large data structures and images.

A lot of these were fixed using `cargo clippy --fix --workspace
--all-targets`, however it often breaks other lints and needs to be run
again. This was then followed up with some manual fixing.

I understand this is a large diff, but all the changes are pretty
trivial. Rust is doing some heavy lifting here for us. Once I get it up
to speed with main, I'd appreciate this getting merged rather sooner
than later.

Release Notes:

- N/A

crates/agent2/src/thread.rs

@@ -679,7 +679,7 @@ impl Thread {
                 .and_then(|model| {
                     let model = SelectedModel {
                         provider: model.provider.clone().into(),
-                        model: model.model.clone().into(),
+                        model: model.model.into(),
                     };
                     registry.select_model(&model, cx)
                 })