refactor: Introduce pre-consume quota and unify relay handlers

This commit introduces a major architectural refactoring to improve quota management, centralize logging, and streamline the relay handling logic.

Key changes:
- **Pre-consume Quota:** Implements a new mechanism to check and reserve user quota *before* making the request to the upstream provider. This ensures more accurate quota deduction and prevents users from exceeding their limits due to concurrent requests.

- **Unified Relay Handlers:** Refactors the relay logic to use generic handlers (e.g., `ChatHandler`, `ImageHandler`) instead of provider-specific implementations. This significantly reduces code duplication and simplifies adding new channels.

- **Centralized Logger:** A new dedicated `logger` package is introduced, and all system logging calls are migrated to use it, moving this responsibility out of the `common` package.

- **Code Reorganization:** DTOs are generalized (e.g., `dalle.go` -> `openai_image.go`) and utility code is moved to more appropriate packages (e.g., `common/http.go` -> `service/http.go`) for better code structure.

relay/channel/gemini/adaptor.go

@@ -78,7 +78,7 @@ func (a *Adaptor) ConvertImageRequest(c *gin.Context, info *relaycommon.RelayInf
 			},
 		},
 		Parameters: dto.GeminiImageParameters{
-			SampleCount:      request.N,
+			SampleCount:      int(request.N),
 			AspectRatio:      aspectRatio,
 			PersonGeneration: "allow_adult", // default allow adult
 		},

relay/channel/gemini/relay-gemini-native.go

@@ -5,6 +5,7 @@ import (
 	"net/http"
 	"one-api/common"
 	"one-api/dto"
+	"one-api/logger"
 	relaycommon "one-api/relay/common"
 	"one-api/relay/helper"
 	"one-api/service"
@@ -17,7 +18,7 @@ import (
 )
 
 func GeminiTextGenerationHandler(c *gin.Context, info *relaycommon.RelayInfo, resp *http.Response) (*dto.Usage, *types.NewAPIError) {
-	defer common.CloseResponseBodyGracefully(resp)
+	defer service.CloseResponseBodyGracefully(resp)
 
 	// 读取响应体
 	responseBody, err := io.ReadAll(resp.Body)
@@ -53,13 +54,13 @@ func GeminiTextGenerationHandler(c *gin.Context, info *relaycommon.RelayInfo, re
 		}
 	}
 
-	common.IOCopyBytesGracefully(c, resp, responseBody)
+	service.IOCopyBytesGracefully(c, resp, responseBody)
 
 	return &usage, nil
 }
 
 func NativeGeminiEmbeddingHandler(c *gin.Context, resp *http.Response, info *relaycommon.RelayInfo) (*dto.Usage, *types.NewAPIError) {
-	defer common.CloseResponseBodyGracefully(resp)
+	defer service.CloseResponseBodyGracefully(resp)
 
 	responseBody, err := io.ReadAll(resp.Body)
 	if err != nil {
@@ -89,7 +90,7 @@ func NativeGeminiEmbeddingHandler(c *gin.Context, resp *http.Response, info *rel
 		}
 	}
 
-	common.IOCopyBytesGracefully(c, resp, responseBody)
+	service.IOCopyBytesGracefully(c, resp, responseBody)
 
 	return usage, nil
 }
@@ -106,7 +107,7 @@ func GeminiTextGenerationStreamHandler(c *gin.Context, info *relaycommon.RelayIn
 		var geminiResponse dto.GeminiChatResponse
 		err := common.UnmarshalJsonStr(data, &geminiResponse)
 		if err != nil {
-			common.LogError(c, "error unmarshalling stream response: "+err.Error())
+			logger.LogError(c, "error unmarshalling stream response: "+err.Error())
 			return false
 		}
 
@@ -140,7 +141,7 @@ func GeminiTextGenerationStreamHandler(c *gin.Context, info *relaycommon.RelayIn
 		// 直接发送 GeminiChatResponse 响应
 		err = helper.StringData(c, data)
 		if err != nil {
-			common.LogError(c, err.Error())
+			logger.LogError(c, err.Error())
 		}
 		info.SendResponseCount++
 		return true

relay/channel/gemini/relay-gemini.go

@@ -9,6 +9,7 @@ import (
 	"one-api/common"
 	"one-api/constant"
 	"one-api/dto"
+	"one-api/logger"
 	"one-api/relay/channel/openai"
 	relaycommon "one-api/relay/common"
 	"one-api/relay/helper"
@@ -901,7 +902,7 @@ func GeminiChatStreamHandler(c *gin.Context, info *relaycommon.RelayInfo, resp *
 		var geminiResponse dto.GeminiChatResponse
 		err := common.UnmarshalJsonStr(data, &geminiResponse)
 		if err != nil {
-			common.LogError(c, "error unmarshalling stream response: "+err.Error())
+			logger.LogError(c, "error unmarshalling stream response: "+err.Error())
 			return false
 		}
 
@@ -945,7 +946,7 @@ func GeminiChatStreamHandler(c *gin.Context, info *relaycommon.RelayInfo, resp *
 				finishReason = constant.FinishReasonToolCalls
 				err = handleStream(c, info, emptyResponse)
 				if err != nil {
-					common.LogError(c, err.Error())
+					logger.LogError(c, err.Error())
 				}
 
 				response.ClearToolCalls()
@@ -957,7 +958,7 @@ func GeminiChatStreamHandler(c *gin.Context, info *relaycommon.RelayInfo, resp *
 
 		err = handleStream(c, info, response)
 		if err != nil {
-			common.LogError(c, err.Error())
+			logger.LogError(c, err.Error())
 		}
 		if isStop {
 			_ = handleStream(c, info, helper.GenerateStopResponse(id, createAt, info.UpstreamModelName, finishReason))
@@ -993,7 +994,7 @@ func GeminiChatStreamHandler(c *gin.Context, info *relaycommon.RelayInfo, resp *
 	response := helper.GenerateFinalUsageResponse(id, createAt, info.UpstreamModelName, *usage)
 	err := handleFinalStream(c, info, response)
 	if err != nil {
-		common.SysError("send final response failed: " + err.Error())
+		logger.SysError("send final response failed: " + err.Error())
 	}
 	//if info.RelayFormat == relaycommon.RelayFormatOpenAI {
 	//	helper.Done(c)
@@ -1007,7 +1008,7 @@ func GeminiChatHandler(c *gin.Context, info *relaycommon.RelayInfo, resp *http.R
 	if err != nil {
 		return nil, types.NewOpenAIError(err, types.ErrorCodeBadResponseBody, http.StatusInternalServerError)
 	}
-	common.CloseResponseBodyGracefully(resp)
+	service.CloseResponseBodyGracefully(resp)
 	if common.DebugEnabled {
 		println(string(responseBody))
 	}
@@ -1057,13 +1058,13 @@ func GeminiChatHandler(c *gin.Context, info *relaycommon.RelayInfo, resp *http.R
 		break
 	}
 
-	common.IOCopyBytesGracefully(c, resp, responseBody)
+	service.IOCopyBytesGracefully(c, resp, responseBody)
 
 	return &usage, nil
 }
 
 func GeminiEmbeddingHandler(c *gin.Context, info *relaycommon.RelayInfo, resp *http.Response) (*dto.Usage, *types.NewAPIError) {
-	defer common.CloseResponseBodyGracefully(resp)
+	defer service.CloseResponseBodyGracefully(resp)
 
 	responseBody, readErr := io.ReadAll(resp.Body)
 	if readErr != nil {
@@ -1107,7 +1108,7 @@ func GeminiEmbeddingHandler(c *gin.Context, info *relaycommon.RelayInfo, resp *h
 		return nil, types.NewOpenAIError(jsonErr, types.ErrorCodeBadResponseBody, http.StatusInternalServerError)
 	}
 
-	common.IOCopyBytesGracefully(c, resp, jsonResponse)
+	service.IOCopyBytesGracefully(c, resp, jsonResponse)
 	return usage, nil
 }