fix: 修复多个关键问题

- 修复前端路由守卫：未登录时不显示提示，直接跳转登录页
- 修复API拦截器：401错误不显示提示，直接跳转
- 增强验证码显示：图片尺寸从120x40增加到200x80
- 增大验证码字体：从28号增加到48号
- 优化验证码字符：排除易混淆的0和1
- 减少干扰线：从5条减少到3条，添加背景色优化
- 增强登录API日志：添加详细的调试日志
- 增强验证码生成和验证日志
- 优化异常处理和错误追踪

影响文件：
- src/router/index.ts
- src/api/request.ts
- app/services/auth_service.py
- app/api/v1/auth.py
- app/schemas/user.py

测试状态：
- 前端构建通过
- 后端语法检查通过
- 验证码显示效果优化完成

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

app/core/security.py

@@ -0,0 +1,178 @@
+"""
+安全相关工具模块
+"""
+from datetime import datetime, timedelta
+from typing import Optional, Dict, Any
+from jose import JWTError, jwt
+from passlib.context import CryptContext
+from fastapi import HTTPException, status
+from app.core.config import settings
+
+# 密码加密上下文
+pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
+
+
+class SecurityManager:
+    """安全管理器"""
+
+    def __init__(self):
+        self.secret_key = settings.SECRET_KEY
+        self.algorithm = settings.ALGORITHM
+        self.access_token_expire_minutes = settings.ACCESS_TOKEN_EXPIRE_MINUTES
+        self.refresh_token_expire_days = settings.REFRESH_TOKEN_EXPIRE_DAYS
+
+    def verify_password(self, plain_password: str, hashed_password: str) -> bool:
+        """
+        验证密码
+
+        Args:
+            plain_password: 明文密码
+            hashed_password: 哈希密码
+
+        Returns:
+            bool: 密码是否匹配
+        """
+        return pwd_context.verify(plain_password, hashed_password)
+
+    def get_password_hash(self, password: str) -> str:
+        """
+        获取密码哈希值
+
+        Args:
+            password: 明文密码
+
+        Returns:
+            str: 哈希后的密码
+        """
+        return pwd_context.hash(password)
+
+    def create_access_token(
+        self,
+        data: Dict[str, Any],
+        expires_delta: Optional[timedelta] = None
+    ) -> str:
+        """
+        创建访问令牌
+
+        Args:
+            data: 要编码的数据
+            expires_delta: 过期时间增量
+
+        Returns:
+            str: JWT令牌
+        """
+        to_encode = data.copy()
+
+        if expires_delta:
+            expire = datetime.utcnow() + expires_delta
+        else:
+            expire = datetime.utcnow() + timedelta(minutes=self.access_token_expire_minutes)
+
+        to_encode.update({
+            "exp": expire,
+            "type": "access"
+        })
+
+        encoded_jwt = jwt.encode(to_encode, self.secret_key, algorithm=self.algorithm)
+        return encoded_jwt
+
+    def create_refresh_token(
+        self,
+        data: Dict[str, Any],
+        expires_delta: Optional[timedelta] = None
+    ) -> str:
+        """
+        创建刷新令牌
+
+        Args:
+            data: 要编码的数据
+            expires_delta: 过期时间增量
+
+        Returns:
+            str: JWT令牌
+        """
+        to_encode = data.copy()
+
+        if expires_delta:
+            expire = datetime.utcnow() + expires_delta
+        else:
+            expire = datetime.utcnow() + timedelta(days=self.refresh_token_expire_days)
+
+        to_encode.update({
+            "exp": expire,
+            "type": "refresh"
+        })
+
+        encoded_jwt = jwt.encode(to_encode, self.secret_key, algorithm=self.algorithm)
+        return encoded_jwt
+
+    def decode_token(self, token: str) -> Dict[str, Any]:
+        """
+        解码令牌
+
+        Args:
+            token: JWT令牌
+
+        Returns:
+            Dict: 解码后的数据
+
+        Raises:
+            HTTPException: 令牌无效或过期
+        """
+        try:
+            payload = jwt.decode(token, self.secret_key, algorithms=[self.algorithm])
+            return payload
+        except JWTError as e:
+            raise HTTPException(
+                status_code=status.HTTP_401_UNAUTHORIZED,
+                detail="无效的认证凭据",
+                headers={"WWW-Authenticate": "Bearer"}
+            )
+
+    def verify_token(self, token: str, token_type: str = "access") -> Dict[str, Any]:
+        """
+        验证令牌
+
+        Args:
+            token: JWT令牌
+            token_type: 令牌类型（access/refresh）
+
+        Returns:
+            Dict: 解码后的数据
+
+        Raises:
+            HTTPException: 令牌无效或类型不匹配
+        """
+        payload = self.decode_token(token)
+
+        if payload.get("type") != token_type:
+            raise HTTPException(
+                status_code=status.HTTP_401_UNAUTHORIZED,
+                detail=f"令牌类型不匹配，期望{token_type}"
+            )
+
+        return payload
+
+
+# 创建全局安全管理器实例
+security_manager = SecurityManager()
+
+
+def get_password_hash(password: str) -> str:
+    """获取密码哈希值（便捷函数）"""
+    return security_manager.get_password_hash(password)
+
+
+def verify_password(plain_password: str, hashed_password: str) -> bool:
+    """验证密码（便捷函数）"""
+    return security_manager.verify_password(plain_password, hashed_password)
+
+
+def create_access_token(data: Dict[str, Any], expires_delta: Optional[timedelta] = None) -> str:
+    """创建访问令牌（便捷函数）"""
+    return security_manager.create_access_token(data, expires_delta)
+
+
+def create_refresh_token(data: Dict[str, Any], expires_delta: Optional[timedelta] = None) -> str:
+    """创建刷新令牌（便捷函数）"""
+    return security_manager.create_refresh_token(data, expires_delta)