Add management API handlers for config and auth file management

- Implemented CRUD operations for authentication files.
- Added endpoints for managing API keys, quotas, proxy settings, and other configurations.
- Enhanced management access with robust validation, remote access control, and persistence support.
- Updated README with new configuration details.

Fixed OpenAI Chat Completions for codex

internal/api/handlers/management/auth_files.go

@@ -0,0 +1,139 @@
+package management
+
+import (
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+	"strings"
+
+	"github.com/gin-gonic/gin"
+)
+
+// List auth files
+func (h *Handler) ListAuthFiles(c *gin.Context) {
+	entries, err := os.ReadDir(h.cfg.AuthDir)
+	if err != nil {
+		c.JSON(500, gin.H{"error": fmt.Sprintf("failed to read auth dir: %v", err)})
+		return
+	}
+	files := make([]gin.H, 0)
+	for _, e := range entries {
+		if e.IsDir() {
+			continue
+		}
+		name := e.Name()
+		if !strings.HasSuffix(strings.ToLower(name), ".json") {
+			continue
+		}
+		if info, errInfo := e.Info(); errInfo == nil {
+			files = append(files, gin.H{"name": name, "size": info.Size(), "modtime": info.ModTime()})
+		}
+	}
+	c.JSON(200, gin.H{"files": files})
+}
+
+// Download single auth file by name
+func (h *Handler) DownloadAuthFile(c *gin.Context) {
+	name := c.Query("name")
+	if name == "" || strings.Contains(name, string(os.PathSeparator)) {
+		c.JSON(400, gin.H{"error": "invalid name"})
+		return
+	}
+	if !strings.HasSuffix(strings.ToLower(name), ".json") {
+		c.JSON(400, gin.H{"error": "name must end with .json"})
+		return
+	}
+	full := filepath.Join(h.cfg.AuthDir, name)
+	data, err := os.ReadFile(full)
+	if err != nil {
+		if os.IsNotExist(err) {
+			c.JSON(404, gin.H{"error": "file not found"})
+		} else {
+			c.JSON(500, gin.H{"error": fmt.Sprintf("failed to read file: %v", err)})
+		}
+		return
+	}
+	c.Header("Content-Disposition", fmt.Sprintf("attachment; filename=\"%s\"", name))
+	c.Data(200, "application/json", data)
+}
+
+// Upload auth file: multipart or raw JSON with ?name=
+func (h *Handler) UploadAuthFile(c *gin.Context) {
+	if file, err := c.FormFile("file"); err == nil && file != nil {
+		name := filepath.Base(file.Filename)
+		if !strings.HasSuffix(strings.ToLower(name), ".json") {
+			c.JSON(400, gin.H{"error": "file must be .json"})
+			return
+		}
+		dst := filepath.Join(h.cfg.AuthDir, name)
+		if errSave := c.SaveUploadedFile(file, dst); errSave != nil {
+			c.JSON(500, gin.H{"error": fmt.Sprintf("failed to save file: %v", errSave)})
+			return
+		}
+		c.JSON(200, gin.H{"status": "ok"})
+		return
+	}
+	name := c.Query("name")
+	if name == "" || strings.Contains(name, string(os.PathSeparator)) {
+		c.JSON(400, gin.H{"error": "invalid name"})
+		return
+	}
+	if !strings.HasSuffix(strings.ToLower(name), ".json") {
+		c.JSON(400, gin.H{"error": "name must end with .json"})
+		return
+	}
+	data, err := io.ReadAll(c.Request.Body)
+	if err != nil {
+		c.JSON(400, gin.H{"error": "failed to read body"})
+		return
+	}
+	dst := filepath.Join(h.cfg.AuthDir, filepath.Base(name))
+	if errWrite := os.WriteFile(dst, data, 0o600); errWrite != nil {
+		c.JSON(500, gin.H{"error": fmt.Sprintf("failed to write file: %v", errWrite)})
+		return
+	}
+	c.JSON(200, gin.H{"status": "ok"})
+}
+
+// Delete auth files: single by name or all
+func (h *Handler) DeleteAuthFile(c *gin.Context) {
+	if all := c.Query("all"); all == "true" || all == "1" || all == "*" {
+		entries, err := os.ReadDir(h.cfg.AuthDir)
+		if err != nil {
+			c.JSON(500, gin.H{"error": fmt.Sprintf("failed to read auth dir: %v", err)})
+			return
+		}
+		deleted := 0
+		for _, e := range entries {
+			if e.IsDir() {
+				continue
+			}
+			name := e.Name()
+			if !strings.HasSuffix(strings.ToLower(name), ".json") {
+				continue
+			}
+			full := filepath.Join(h.cfg.AuthDir, name)
+			if err = os.Remove(full); err == nil {
+				deleted++
+			}
+		}
+		c.JSON(200, gin.H{"status": "ok", "deleted": deleted})
+		return
+	}
+	name := c.Query("name")
+	if name == "" || strings.Contains(name, string(os.PathSeparator)) {
+		c.JSON(400, gin.H{"error": "invalid name"})
+		return
+	}
+	full := filepath.Join(h.cfg.AuthDir, filepath.Base(name))
+	if err := os.Remove(full); err != nil {
+		if os.IsNotExist(err) {
+			c.JSON(404, gin.H{"error": "file not found"})
+		} else {
+			c.JSON(500, gin.H{"error": fmt.Sprintf("failed to remove file: %v", err)})
+		}
+		return
+	}
+	c.JSON(200, gin.H{"status": "ok"})
+}