feat: 新增支持codex转发

backend/internal/pkg/openai/constants.go

@@ -0,0 +1,42 @@
+package openai
+
+import _ "embed"
+
+// Model represents an OpenAI model
+type Model struct {
+	ID          string `json:"id"`
+	Object      string `json:"object"`
+	Created     int64  `json:"created"`
+	OwnedBy     string `json:"owned_by"`
+	Type        string `json:"type"`
+	DisplayName string `json:"display_name"`
+}
+
+// DefaultModels OpenAI models list
+var DefaultModels = []Model{
+	{ID: "gpt-5.2", Object: "model", Created: 1733875200, OwnedBy: "openai", Type: "model", DisplayName: "GPT-5.2"},
+	{ID: "gpt-5.2-codex", Object: "model", Created: 1733011200, OwnedBy: "openai", Type: "model", DisplayName: "GPT-5.2 Codex"},
+	{ID: "gpt-5.1-codex-max", Object: "model", Created: 1730419200, OwnedBy: "openai", Type: "model", DisplayName: "GPT-5.1 Codex Max"},
+	{ID: "gpt-5.1-codex", Object: "model", Created: 1730419200, OwnedBy: "openai", Type: "model", DisplayName: "GPT-5.1 Codex"},
+	{ID: "gpt-5.1", Object: "model", Created: 1731456000, OwnedBy: "openai", Type: "model", DisplayName: "GPT-5.1"},
+	{ID: "gpt-5.1-codex-mini", Object: "model", Created: 1730419200, OwnedBy: "openai", Type: "model", DisplayName: "GPT-5.1 Codex Mini"},
+	{ID: "gpt-5", Object: "model", Created: 1722988800, OwnedBy: "openai", Type: "model", DisplayName: "GPT-5"},
+}
+
+// DefaultModelIDs returns the default model ID list
+func DefaultModelIDs() []string {
+	ids := make([]string, len(DefaultModels))
+	for i, m := range DefaultModels {
+		ids[i] = m.ID
+	}
+	return ids
+}
+
+// DefaultTestModel default model for testing OpenAI accounts
+const DefaultTestModel = "gpt-5.1-codex"
+
+// DefaultInstructions default instructions for non-Codex CLI requests
+// Content loaded from instructions.txt at compile time
+//
+//go:embed instructions.txt
+var DefaultInstructions string