update:1.优化 AI 流式生成和进度显示系统 2.新增写作风格系统提示词支持 3.灵感模式功能增强,支持灵感重写 4.设置页面功能扩展，新增Gemini适配器 5.提示词模板系统优化，调整灵感模式提示词

backend/app/services/ai_config.py

@@ -0,0 +1,44 @@
+"""AI 服务配置管理"""
+from dataclasses import dataclass, field
+from typing import Optional
+
+
+@dataclass
+class HTTPClientConfig:
+    """HTTP 客户端配置"""
+    connect_timeout: float = 90.0
+    read_timeout: float = 300.0
+    write_timeout: float = 90.0
+    pool_timeout: float = 90.0
+    max_keepalive_connections: int = 50
+    max_connections: int = 100
+    keepalive_expiry: float = 60.0
+
+
+@dataclass
+class RetryConfig:
+    """重试配置"""
+    max_retries: int = 3
+    base_delay: float = 0.2
+    max_delay: float = 10.0
+    exponential_base: int = 2
+    non_retryable_status_codes: tuple = field(default_factory=lambda: (401, 403, 404))
+
+
+@dataclass
+class RateLimitConfig:
+    """限流配置"""
+    max_concurrent_requests: int = 5
+    request_delay: float = 0.2
+
+
+@dataclass
+class AIClientConfig:
+    """AI 客户端完整配置"""
+    http: HTTPClientConfig = field(default_factory=HTTPClientConfig)
+    retry: RetryConfig = field(default_factory=RetryConfig)
+    rate_limit: RateLimitConfig = field(default_factory=RateLimitConfig)
+
+
+# 全局默认配置
+default_config = AIClientConfig()