Never store requests (#3212)

When item ids are sent to Responses API it will load them from the
database ignoring the provided values. This adds extra latency.

Not having the mode to store requests also allows us to simplify the
code.

## Breaking change

The `disable_response_storage` configuration option is removed.

codex-rs/core/tests/suite/client.rs

@@ -224,19 +224,16 @@ async fn resume_includes_initial_messages_and_sends_prior_items() {
     let expected_input = serde_json::json!([
         {
             "type": "message",
-            "id": null,
             "role": "user",
             "content": [{ "type": "input_text", "text": "resumed user message" }]
         },
         {
             "type": "message",
-            "id": null,
             "role": "assistant",
             "content": [{ "type": "output_text", "text": "resumed assistant message" }]
         },
         {
             "type": "message",
-            "id": null,
             "role": "user",
             "content": [{ "type": "input_text", "text": "hello" }]
         }
@@ -496,7 +493,6 @@ async fn chatgpt_auth_sends_correct_request() {
         "Bearer Access Token"
     );
     assert_eq!(request_chatgpt_account_id.to_str().unwrap(), "account_id");
-    assert!(!request_body["store"].as_bool().unwrap());
     assert!(request_body["stream"].as_bool().unwrap());
     assert_eq!(
         request_body["include"][0].as_str().unwrap(),
@@ -578,14 +574,6 @@ async fn prefers_chatgpt_token_when_config_prefers_chatgpt() {
         .unwrap();
 
     wait_for_event(&codex, |ev| matches!(ev, EventMsg::TaskComplete(_))).await;
-
-    // verify request body flags
-    let request = &server.received_requests().await.unwrap()[0];
-    let request_body = request.body_json::<serde_json::Value>().unwrap();
-    assert!(
-        !request_body["store"].as_bool().unwrap(),
-        "store should be false for ChatGPT auth"
-    );
 }
 
 #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
@@ -662,14 +650,6 @@ async fn prefers_apikey_when_config_prefers_apikey_even_with_chatgpt_tokens() {
         .unwrap();
 
     wait_for_event(&codex, |ev| matches!(ev, EventMsg::TaskComplete(_))).await;
-
-    // verify request body flags
-    let request = &server.received_requests().await.unwrap()[0];
-    let request_body = request.body_json::<serde_json::Value>().unwrap();
-    assert!(
-        request_body["store"].as_bool().unwrap(),
-        "store should be true for API key auth"
-    );
 }
 
 #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
@@ -990,31 +970,26 @@ async fn history_dedupes_streamed_and_final_messages_across_turns() {
     let r3_tail_expected = serde_json::json!([
         {
             "type": "message",
-            "id": null,
             "role": "user",
             "content": [{"type":"input_text","text":"U1"}]
         },
         {
             "type": "message",
-            "id": null,
             "role": "assistant",
             "content": [{"type":"output_text","text":"Hey there!\n"}]
         },
         {
             "type": "message",
-            "id": null,
             "role": "user",
             "content": [{"type":"input_text","text":"U2"}]
         },
         {
             "type": "message",
-            "id": null,
             "role": "assistant",
             "content": [{"type":"output_text","text":"Hey there!\n"}]
         },
         {
             "type": "message",
-            "id": null,
             "role": "user",
             "content": [{"type":"input_text","text":"U3"}]
         }

codex-rs/core/tests/suite/prompt_caching.rs

@@ -289,20 +289,17 @@ async fn prefixes_context_and_instructions_once_and_consistently_across_requests
 
     let expected_env_msg = serde_json::json!({
         "type": "message",
-        "id": serde_json::Value::Null,
         "role": "user",
         "content": [ { "type": "input_text", "text": expected_env_text } ]
     });
     let expected_ui_msg = serde_json::json!({
         "type": "message",
-        "id": serde_json::Value::Null,
         "role": "user",
         "content": [ { "type": "input_text", "text": expected_ui_text } ]
     });
 
     let expected_user_message_1 = serde_json::json!({
         "type": "message",
-        "id": serde_json::Value::Null,
         "role": "user",
         "content": [ { "type": "input_text", "text": "hello 1" } ]
     });
@@ -314,7 +311,6 @@ async fn prefixes_context_and_instructions_once_and_consistently_across_requests
 
     let expected_user_message_2 = serde_json::json!({
         "type": "message",
-        "id": serde_json::Value::Null,
         "role": "user",
         "content": [ { "type": "input_text", "text": "hello 2" } ]
     });
@@ -424,7 +420,6 @@ async fn overrides_turn_context_but_keeps_cached_prefix_and_key_constant() {
     // as the prefix of the second request, ensuring cache hit potential.
     let expected_user_message_2 = serde_json::json!({
         "type": "message",
-        "id": serde_json::Value::Null,
         "role": "user",
         "content": [ { "type": "input_text", "text": "hello 2" } ]
     });
@@ -438,7 +433,6 @@ async fn overrides_turn_context_but_keeps_cached_prefix_and_key_constant() {
 </environment_context>"#;
     let expected_env_msg_2 = serde_json::json!({
         "type": "message",
-        "id": serde_json::Value::Null,
         "role": "user",
         "content": [ { "type": "input_text", "text": expected_env_text_2 } ]
     });
@@ -543,7 +537,6 @@ async fn per_turn_overrides_keep_cached_prefix_and_key_constant() {
     // as the prefix of the second request.
     let expected_user_message_2 = serde_json::json!({
         "type": "message",
-        "id": serde_json::Value::Null,
         "role": "user",
         "content": [ { "type": "input_text", "text": "hello 2" } ]
     });