fix: CI/CD build errors

- Simplified go.mod with all dependencies
- Fixed generateRandomSecret function
- Updated Dockerfile to use debian bookworm
- Simplified CI workflow to single job
- Fixed Gitea Actions syntax (github.ref)

cmd/server/main.go

@@ -1,9 +1,10 @@
 package main
 
 import (
+	"crypto/rand"
+	"encoding/hex"
 	"fmt"
 	"log"
-	"os"
 
 	"anticaptcha/internal/captcha"
 	"anticaptcha/internal/config"
@@ -54,18 +55,19 @@ func main() {
 
 	// 静态文件服务（前端）
 	r.Static("/assets", "./web/dist/assets")
-	r.StaticFile("/", "./web/dist/index.html")
-	r.StaticFile("/favicon.ico", "./web/dist/favicon.ico")
+	r.NoRoute(func(c *gin.Context) {
+		c.File("./web/dist/index.html")
+	})
 
 	// API 路由
 	captchaHandler := handler.NewCaptchaHandler(captcha.NewHandler("./models"))
 	captchaHandler.RegisterRoutes(r.Group(""), true)
 
 	// 安装路由
-	r.GET("/install", func(c *gin.Context) {
-		c.File("./web/dist/index.html")
-	})
 	r.POST("/api/install", handleInstall)
+	r.GET("/api/install/check", func(c *gin.Context) {
+		c.JSON(200, gin.H{"installed": config.IsInstalled()})
+	})
 
 	// 健康检查
 	r.GET("/health", func(c *gin.Context) {
@@ -77,7 +79,7 @@ func main() {
 	if config.Cfg != nil {
 		addr = fmt.Sprintf("%s:%d", config.Cfg.Server.Host, config.Cfg.Server.Port)
 	}
-	
+
 	fmt.Printf(`
     ╔════════════════════════════════════════════════════════════════╗
     ║           AntiCaptcha Server v1.0.0                            ║
@@ -169,15 +171,11 @@ func handleInstall(c *gin.Context) {
 
 	c.JSON(200, gin.H{
 		"message": "安装成功",
-		"config":  cfg,
 	})
 }
 
 func generateRandomSecret() string {
-	const charset = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"
-	b := make([]byte, 64)
-	for i := range b {
-		b[i] = charset[os.New(0).UnixNano()%int64(len(charset))]
-	}
-	return string(b)
+	b := make([]byte, 32)
+	rand.Read(b)
+	return hex.EncodeToString(b)
 }