feat: enhance security with IP banning, ownership checks, and SSRF protection

Add comprehensive security improvements across the application:

- **IP-based login protection**: Implement IP ban system tracking login failures, auto-banning after threshold exceeded
- **Ownership verification**: Add userID parameter to Delete/Update operations for posts and comments to prevent unauthorized modifications
- **SSRF protection**: Add URL and resolved host validation for image URLs in chat and OpenAI client
- **SQL injection prevention**: Add EscapeLikeWildcard utility to escape special characters in LIKE queries
- **HTTP security**: Configure server timeouts and add security headers middleware
- **Rate limiting**: Refactor to support configurable duration and per-endpoint rate limits for auth routes
- **Error handling**: Standardize error responses using HandleError and proper error types

internal/handler/user_handler.go

@@ -10,6 +10,7 @@ import (
 	"github.com/gin-gonic/gin"
 
 	"with_you/internal/dto"
+	"with_you/internal/middleware"
 	"with_you/internal/model"
 	"with_you/internal/pkg/response"
 	"with_you/internal/service"
@@ -153,10 +154,13 @@ func (h *UserHandler) Login(c *gin.Context) {
 
 	user, err := h.userService.Login(c.Request.Context(), account, req.Password)
 	if err != nil {
+		middleware.RecordLoginFailure(c.ClientIP())
 		response.HandleError(c, err, "failed to login")
 		return
 	}
 
+	middleware.ResetLoginFailures(c.ClientIP())
+
 	// 生成Token
 	accessToken, _ := h.jwtService.GenerateAccessToken(user.ID, user.Username)
 	refreshToken, _ := h.jwtService.GenerateRefreshToken(user.ID, user.Username)