Add cloud tasks (#3197)

Adds a TUI for managing, applying, and creating cloud tasks

codex-rs/backend-client/src/lib.rs

@@ -0,0 +1,9 @@
+mod client;
+pub mod types;
+
+pub use client::Client;
+pub use types::CodeTaskDetailsResponse;
+pub use types::CodeTaskDetailsResponseExt;
+pub use types::PaginatedListTaskListItem;
+pub use types::TaskListItem;
+pub use types::TurnAttemptsSiblingTurnsResponse;