Preserve usage limit windows in turn and compaction analytics (#48174)

## Why

Usage limit errors discarded the server-selected window responsible for the limit, leaving turn and compaction analytics unable to distinguish five-hour limits from weekly limits.

## What changed

Preserve optional `limit_window_minutes` from usage limit error responses in `UsageLimitReachedError` and report it as `usage_limit_window_minutes` in turn and compaction events. Accept unsigned integers that fit in `u16`; treat missing, null, malformed, or out-of-range values as unknown. Events for other error kinds report `null`.

## Testing

Add coverage for HTTP and wrapped WebSocket error mapping, analytics serialization and reduction, and app-server propagation to turn and local/remote compaction events. Cases include five-hour and weekly windows, missing or invalid values, and unrelated errors.

GitOrigin-RevId: a32066a007559d91a3c868a756bfd0f976777176

codex-rs/codex-api/src/api_bridge.rs

@@ -204,6 +204,12 @@ fn map_api_error_details(err: ApiError) -> CodexErr {
                             return CodexErr::UsageLimitReached(UsageLimitReachedError {
                                 plan_type: err.error.plan_type,
                                 resets_at,
+                                limit_window_minutes: err
+                                    .error
+                                    .limit_window_minutes
+                                    .as_ref()
+                                    .and_then(Value::as_u64)
+                                    .and_then(|minutes| u16::try_from(minutes).ok()),
                                 rate_limits: rate_limits.map(Box::new),
                                 promo_message,
                                 rate_limit_reached_type,
@@ -340,4 +346,5 @@ struct UsageErrorBody {
     error_type: Option<String>,
     plan_type: Option<PlanType>,
     resets_at: Option<i64>,
+    limit_window_minutes: Option<Value>,
 }