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/request_logging_test.go

@@ -0,0 +1,138 @@
+package middleware
+
+import (
+	"io"
+	"net/http"
+	"net/url"
+	"strings"
+	"testing"
+)
+
+func TestShouldSkipMethodForRequestLogging(t *testing.T) {
+	tests := []struct {
+		name string
+		req  *http.Request
+		skip bool
+	}{
+		{
+			name: "nil request",
+			req:  nil,
+			skip: true,
+		},
+		{
+			name: "post request should not skip",
+			req: &http.Request{
+				Method: http.MethodPost,
+				URL:    &url.URL{Path: "/v1/responses"},
+			},
+			skip: false,
+		},
+		{
+			name: "plain get should skip",
+			req: &http.Request{
+				Method: http.MethodGet,
+				URL:    &url.URL{Path: "/v1/models"},
+				Header: http.Header{},
+			},
+			skip: true,
+		},
+		{
+			name: "responses websocket upgrade should not skip",
+			req: &http.Request{
+				Method: http.MethodGet,
+				URL:    &url.URL{Path: "/v1/responses"},
+				Header: http.Header{"Upgrade": []string{"websocket"}},
+			},
+			skip: false,
+		},
+		{
+			name: "responses get without upgrade should skip",
+			req: &http.Request{
+				Method: http.MethodGet,
+				URL:    &url.URL{Path: "/v1/responses"},
+				Header: http.Header{},
+			},
+			skip: true,
+		},
+	}
+
+	for i := range tests {
+		got := shouldSkipMethodForRequestLogging(tests[i].req)
+		if got != tests[i].skip {
+			t.Fatalf("%s: got skip=%t, want %t", tests[i].name, got, tests[i].skip)
+		}
+	}
+}
+
+func TestShouldCaptureRequestBody(t *testing.T) {
+	tests := []struct {
+		name          string
+		loggerEnabled bool
+		req           *http.Request
+		want          bool
+	}{
+		{
+			name:          "logger enabled always captures",
+			loggerEnabled: true,
+			req: &http.Request{
+				Body:          io.NopCloser(strings.NewReader("{}")),
+				ContentLength: -1,
+				Header:        http.Header{"Content-Type": []string{"application/json"}},
+			},
+			want: true,
+		},
+		{
+			name:          "nil request",
+			loggerEnabled: false,
+			req:           nil,
+			want:          false,
+		},
+		{
+			name:          "small known size json in error-only mode",
+			loggerEnabled: false,
+			req: &http.Request{
+				Body:          io.NopCloser(strings.NewReader("{}")),
+				ContentLength: 2,
+				Header:        http.Header{"Content-Type": []string{"application/json"}},
+			},
+			want: true,
+		},
+		{
+			name:          "large known size skipped in error-only mode",
+			loggerEnabled: false,
+			req: &http.Request{
+				Body:          io.NopCloser(strings.NewReader("x")),
+				ContentLength: maxErrorOnlyCapturedRequestBodyBytes + 1,
+				Header:        http.Header{"Content-Type": []string{"application/json"}},
+			},
+			want: false,
+		},
+		{
+			name:          "unknown size skipped in error-only mode",
+			loggerEnabled: false,
+			req: &http.Request{
+				Body:          io.NopCloser(strings.NewReader("x")),
+				ContentLength: -1,
+				Header:        http.Header{"Content-Type": []string{"application/json"}},
+			},
+			want: false,
+		},
+		{
+			name:          "multipart skipped in error-only mode",
+			loggerEnabled: false,
+			req: &http.Request{
+				Body:          io.NopCloser(strings.NewReader("x")),
+				ContentLength: 1,
+				Header:        http.Header{"Content-Type": []string{"multipart/form-data; boundary=abc"}},
+			},
+			want: false,
+		},
+	}
+
+	for i := range tests {
+		got := shouldCaptureRequestBody(tests[i].loggerEnabled, tests[i].req)
+		if got != tests[i].want {
+			t.Fatalf("%s: got %t, want %t", tests[i].name, got, tests[i].want)
+		}
+	}
+}