feat: 添加自定义Auto配置功能

新增功能:
- Auto配置管理页面 (/auto-profiles)
- 创建自定义auto模式，如auto-fast, auto-cheap
- 指定候选提供商和优先级
- 支持按优先级/随机选择策略

API:
- GET/POST /api/auto-profiles
- GET/PUT/DELETE /api/auto-profiles/<name>

改进:
- 主服务支持自定义auto模式路由
- 模型列表显示所有auto配置

app.py

@@ -16,7 +16,7 @@ import sys
 # 添加配置路径
 sys.path.insert(0, str(Path(__file__).parent))
 from config.settings import (
-    get_providers, get_model_aliases, SERVER_CONFIG, 
+    get_providers, get_model_aliases, get_auto_profiles, SERVER_CONFIG, 
     LOG_CONFIG, RETRY_CONFIG
 )
 
@@ -28,15 +28,17 @@ CONFIG_CACHE_TTL = 5
 _last_config_load = 0
 _cached_providers = []
 _cached_aliases = {}
+_cached_auto_profiles = {}
 
 def refresh_config():
     """动态刷新配置（支持后台管理修改）"""
-    global _last_config_load, _cached_providers, _cached_aliases, provider_status
+    global _last_config_load, _cached_providers, _cached_aliases, _cached_auto_profiles, provider_status
     
     current_time = time.time()
     if current_time - _last_config_load > CONFIG_CACHE_TTL:
         _cached_providers = get_providers()
         _cached_aliases = get_model_aliases()
+        _cached_auto_profiles = get_auto_profiles()
         _last_config_load = current_time
         
         # 更新提供商状态缓存（新增的提供商）
@@ -78,8 +80,8 @@ def get_provider_for_model(model_name):
     resolved_model = _cached_aliases.get(model_name, model_name)
     
     # auto模式：按优先级选择可用提供商
-    if resolved_model == 'auto':
-        return get_available_provider()
+    if resolved_model == 'auto' or resolved_model.startswith('auto-'):
+        return get_available_provider_for_auto(resolved_model)
     
     # 查找支持该模型的提供商
     sorted_providers = sorted(_cached_providers, key=lambda x: x['priority'])
@@ -105,21 +107,52 @@ def get_provider_for_model(model_name):
     return None, None
 
 
-def get_available_provider():
-    """获取可用的提供商（按优先级）"""
+def get_available_provider_for_auto(auto_name='auto'):
+    """获取auto模式下的可用提供商（支持自定义auto配置）"""
     refresh_config()
     
+    # 获取auto配置
+    profile = _cached_auto_profiles.get(auto_name, _cached_auto_profiles.get('auto', {}))
+    
+    # 获取允许的提供商
+    allowed_providers = profile.get('providers', ['*'])
+    
+    # 筛选提供商
     sorted_providers = sorted(_cached_providers, key=lambda x: x['priority'])
+    candidates = []
     
     for provider in sorted_providers:
-        if provider['enabled'] and provider_status.get(provider['name'], {}).get('available', True):
-            return provider, provider['default_model']
+        if not provider['enabled']:
+            continue
+        if not provider_status.get(provider['name'], {}).get('available', True):
+            continue
+        
+        # 检查是否在允许列表中
+        if '*' in allowed_providers:
+            candidates.append(provider)
+        elif provider.get('id') in allowed_providers or provider['name'] in allowed_providers:
+            candidates.append(provider)
     
-    # 如果都不可用，返回第一个尝试（让错误信息传递）
-    if sorted_providers:
-        return sorted_providers[0], sorted_providers[0]['default_model']
+    # 根据策略选择
+    strategy = profile.get('strategy', 'priority')
     
-    return None, None
+    if not candidates:
+        # 如果没有候选，返回第一个尝试（让错误信息传递）
+        if sorted_providers:
+            return sorted_providers[0], sorted_providers[0]['default_model']
+        return None, None
+    
+    if strategy == 'priority':
+        # 按优先级选择第一个
+        return candidates[0], candidates[0]['default_model']
+    elif strategy == 'random':
+        # 随机选择
+        import random
+        selected = random.choice(candidates)
+        return selected, selected['default_model']
+    else:
+        # 默认按优先级
+        return candidates[0], candidates[0]['default_model']
 
 
 def mark_provider_error(provider_name, error):
@@ -225,6 +258,18 @@ def list_models():
     models_list = []
     added_models = set()
     
+    # 添加所有auto配置
+    for profile_name, profile in _cached_auto_profiles.items():
+        if profile_name not in added_models:
+            models_list.append({
+                "id": profile_name,
+                "object": "model",
+                "created": int(time.time()),
+                "owned_by": "proxy",
+                "description": profile.get('description', 'Auto-select available model')
+            })
+            added_models.add(profile_name)
+    
     for provider in _cached_providers:
         if not provider['enabled']:
             continue
@@ -238,16 +283,6 @@ def list_models():
                 })
                 added_models.add(model)
     
-    # 添加auto模型
-    if "auto" not in added_models:
-        models_list.insert(0, {
-            "id": "auto",
-            "object": "model",
-            "created": int(time.time()),
-            "owned_by": "proxy",
-            "description": "Auto-select available model by priority"
-        })
-    
     return jsonify({
         "object": "list",
         "data": models_list
@@ -310,7 +345,7 @@ def chat_completions():
                     tried_providers.append(provider['name'])
                     
                     # 尝试下一个提供商
-                    next_provider, next_model = get_available_provider()
+                    next_provider, next_model = get_available_provider_for_auto('auto')
                     if next_provider and next_provider['name'] not in tried_providers:
                         provider = next_provider
                         resolved_model = next_model
@@ -328,7 +363,7 @@ def chat_completions():
                 tried_providers.append(provider['name'])
                 
                 # 尝试下一个提供商
-                next_provider, next_model = get_available_provider()
+                next_provider, next_model = get_available_provider_for_auto('auto')
                 if next_provider and next_provider['name'] not in tried_providers:
                     provider = next_provider
                     resolved_model = next_model