feat: make it possible to set disable_response_storage = true in config.toml (#714)

https://github.com/openai/codex/pull/642 introduced support for the
`--disable-response-storage` flag, but if you are a ZDR customer, it is
tedious to set this every time, so this PR makes it possible to set this
once in `config.toml` and be done with it.

Incidentally, this tidies things up such that now `init_codex()` takes
only one parameter: `Config`.

codex-rs/core/src/codex_wrapper.rs

@@ -15,10 +15,7 @@ use tokio::sync::Notify;
 /// Returns the wrapped [`Codex`] **and** the `SessionInitialized` event that
 /// is received as a response to the initial `ConfigureSession` submission so
 /// that callers can surface the information to the UI.
-pub async fn init_codex(
-    config: Config,
-    disable_response_storage: bool,
-) -> anyhow::Result<(CodexWrapper, Event, Arc<Notify>)> {
+pub async fn init_codex(config: Config) -> anyhow::Result<(CodexWrapper, Event, Arc<Notify>)> {
     let ctrl_c = notify_on_sigint();
     let codex = CodexWrapper::new(Codex::spawn(ctrl_c.clone())?);
     let init_id = codex
@@ -27,7 +24,7 @@ pub async fn init_codex(
             instructions: config.instructions.clone(),
             approval_policy: config.approval_policy,
             sandbox_policy: config.sandbox_policy,
-            disable_response_storage,
+            disable_response_storage: config.disable_response_storage,
         })
         .await?;