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.

middleware/utils.go

@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"github.com/gin-gonic/gin"
 	"one-api/common"
+	"one-api/logger"
 )
 
 func abortWithOpenAiMessage(c *gin.Context, statusCode int, message string) {
@@ -15,7 +16,7 @@ func abortWithOpenAiMessage(c *gin.Context, statusCode int, message string) {
 		},
 	})
 	c.Abort()
-	common.LogError(c.Request.Context(), fmt.Sprintf("user %d | %s", userId, message))
+	logger.LogError(c.Request.Context(), fmt.Sprintf("user %d | %s", userId, message))
 }
 
 func abortWithMidjourneyMessage(c *gin.Context, statusCode int, code int, description string) {
@@ -25,5 +26,5 @@ func abortWithMidjourneyMessage(c *gin.Context, statusCode int, code int, descri
 		"code":        code,
 	})
 	c.Abort()
-	common.LogError(c.Request.Context(), description)
+	logger.LogError(c.Request.Context(), description)
 }