chore: enable clippy::redundant_clone (#3489)

Created this PR by:

- adding `redundant_clone` to `[workspace.lints.clippy]` in
`cargo-rs/Cargol.toml`
- running `cargo clippy --tests --fix`
- running `just fmt`

Though I had to clean up one instance of the following that resulted:

```rust
let codex = codex;
```

codex-rs/tui/src/bottom_pane/mod.rs

@@ -564,7 +564,7 @@ mod tests {
         let (tx_raw, rx) = unbounded_channel::<AppEvent>();
         let tx = AppEventSender::new(tx_raw);
         let mut pane = BottomPane::new(BottomPaneParams {
-            app_event_tx: tx.clone(),
+            app_event_tx: tx,
             frame_requester: FrameRequester::test_dummy(),
             has_input_focus: true,
             enhanced_keys_supported: false,