feat: single app-server bootstrap in TUI (#16582)

Before this, the TUI was starting 2 app-server. One to check the login
status and one to actually start the session

This PR make only one app-server startup and defer the login check in
async, outside of the frame rendering path

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Co-authored-by: Codex <noreply@openai.com>

codex-rs/execpolicy/src/lib.rs

@@ -5,7 +5,7 @@ pub(crate) mod execpolicycheck;
 mod executable_name;
 pub(crate) mod parser;
 pub(crate) mod policy;
-pub(crate) mod rule;
+pub mod rule;
 
 pub use amend::AmendError;
 pub use amend::blocking_append_allow_prefix_rule;