feat(logging, executor): add request logging tests and WebSocket-based Codex executor

- Introduced unit tests for request logging middleware to enhance coverage.
- Added WebSocket-based Codex executor to support Responses API upgrade.
- Updated middleware logic to selectively capture request bodies for memory efficiency.
- Enhanced Codex configuration handling with new WebSocket attributes.

internal/api/middleware/response_writer_test.go

@@ -0,0 +1,43 @@
+package middleware
+
+import (
+	"net/http/httptest"
+	"testing"
+
+	"github.com/gin-gonic/gin"
+)
+
+func TestExtractRequestBodyPrefersOverride(t *testing.T) {
+	gin.SetMode(gin.TestMode)
+	recorder := httptest.NewRecorder()
+	c, _ := gin.CreateTestContext(recorder)
+
+	wrapper := &ResponseWriterWrapper{
+		requestInfo: &RequestInfo{Body: []byte("original-body")},
+	}
+
+	body := wrapper.extractRequestBody(c)
+	if string(body) != "original-body" {
+		t.Fatalf("request body = %q, want %q", string(body), "original-body")
+	}
+
+	c.Set(requestBodyOverrideContextKey, []byte("override-body"))
+	body = wrapper.extractRequestBody(c)
+	if string(body) != "override-body" {
+		t.Fatalf("request body = %q, want %q", string(body), "override-body")
+	}
+}
+
+func TestExtractRequestBodySupportsStringOverride(t *testing.T) {
+	gin.SetMode(gin.TestMode)
+	recorder := httptest.NewRecorder()
+	c, _ := gin.CreateTestContext(recorder)
+
+	wrapper := &ResponseWriterWrapper{}
+	c.Set(requestBodyOverrideContextKey, "override-as-string")
+
+	body := wrapper.extractRequestBody(c)
+	if string(body) != "override-as-string" {
+		t.Fatalf("request body = %q, want %q", string(body), "override-as-string")
+	}
+}