feat: support multiple rate limits (#11260)

Added multi-limit support end-to-end by carrying limit_name in
rate-limit snapshots and handling multiple buckets instead of only
codex.
Extended /usage client parsing to consume additional_rate_limits
Updated TUI /status and in-memory state to store/render per-limit
snapshots
Extended app-server rate-limit read response: kept rate_limits and added
rate_limits_by_name.
Adjusted usage-limit error messaging for non-default codex limit buckets

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

@@ -1509,6 +1509,8 @@ async fn token_count_includes_rate_limits_snapshot() {
         json!({
             "info": null,
             "rate_limits": {
+                "limit_id": "codex",
+                "limit_name": null,
                 "primary": {
                     "used_percent": 12.5,
                     "window_minutes": 10,
@@ -1558,6 +1560,8 @@ async fn token_count_includes_rate_limits_snapshot() {
                 "model_context_window": 258400
             },
             "rate_limits": {
+                "limit_id": "codex",
+                "limit_name": null,
                 "primary": {
                     "used_percent": 12.5,
                     "window_minutes": 10,
@@ -1630,6 +1634,8 @@ async fn usage_limit_error_emits_rate_limit_event() -> anyhow::Result<()> {
     let codex = codex_fixture.codex.clone();
 
     let expected_limits = json!({
+        "limit_id": "codex",
+        "limit_name": null,
         "primary": {
             "used_percent": 100.0,
             "window_minutes": 15,

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

@@ -486,6 +486,8 @@ async fn responses_websocket_usage_limit_error_emits_rate_limit_event() {
         json!({
             "info": null,
             "rate_limits": {
+                "limit_id": "codex",
+                "limit_name": null,
                 "primary": {
                     "used_percent": 100.0,
                     "window_minutes": 15,