feat: enhance text protocol conversion and advanced custom routing (#5825)

* refactor: consolidate relay protocol converters

* refactor relayconvert text converters

* feat: refine relay converters and advanced custom routing

* refactor: enhance logging and add thought signature handling for Gemini requests

* refactor: enhance channel cache and pricing endpoint handling for advanced custom models

* feat: preserve billing usage semantics

* feat: add protocol-aware billing usage

* Delete useless files

* chore: update action versions in workflow files

* chore: update Docker action versions in workflow files

* fix: harden billing usage settlement and hot-path route matching

- estimate Gemini completion tokens locally when billable usageMetadata is
  prompt-only but output content was received (e.g. client aborts the stream
  before the final chunk), and rebuild the attached billing_usage as estimated
  so settlement does not bill zero output tokens
- guard NewClaudeMessagesBillingUsage against all-zero ClaudeUsage, matching
  the OpenAI/Gemini constructors, so a zero billing_usage cannot override a
  non-zero top-level usage during settlement
- cache compiled advanced-custom route model regexes; they run on the request
  hot path and were recompiled per request
- move the effectiveBillingUsage remap to PostTextConsumeQuota only, and
  document that calculateTextQuotaSummary expects remapped usage
- document the updatePricingLock -> channelSyncLock lock ordering that
  InitChannelCache/CacheUpdateChannel rely on, and the aux-struct pitfall in
  GeminiChatResponse.UnmarshalJSON

service/request_converter.go

@@ -0,0 +1,54 @@
+package service
+
+import (
+	"fmt"
+
+	"github.com/QuantumNous/new-api/dto"
+	relaycommon "github.com/QuantumNous/new-api/relay/common"
+	"github.com/QuantumNous/new-api/service/relayconvert"
+	"github.com/QuantumNous/new-api/types"
+	"github.com/gin-gonic/gin"
+)
+
+func init() {
+	relayconvert.SetMediaResolver(relayconvert.MediaResolver{
+		GetBase64Data:        GetBase64Data,
+		DecodeBase64FileData: DecodeBase64FileData,
+	})
+}
+
+func ConvertRequest(c *gin.Context, info *relaycommon.RelayInfo, target types.RelayFormat, request any) (*relayconvert.RequestResult, error) {
+	return relayconvert.ConvertRequest(c, info, target, request)
+}
+
+func ConvertRequestByID(c *gin.Context, info *relaycommon.RelayInfo, converter string, request any) (*relayconvert.RequestResult, error) {
+	return relayconvert.ConvertRequestByID(c, info, converter, request)
+}
+
+func ConvertRequestVia(c *gin.Context, info *relaycommon.RelayInfo, request any, path ...types.RelayFormat) (*relayconvert.RequestResult, error) {
+	return relayconvert.ConvertRequestVia(c, info, request, path...)
+}
+
+func ClaudeToOpenAIRequest(claudeRequest dto.ClaudeRequest, info *relaycommon.RelayInfo) (*dto.GeneralOpenAIRequest, error) {
+	result, err := ConvertRequest(nil, info, types.RelayFormatOpenAI, &claudeRequest)
+	if err != nil {
+		return nil, err
+	}
+	openAIRequest, ok := result.Value.(*dto.GeneralOpenAIRequest)
+	if !ok {
+		return nil, fmt.Errorf("expected OpenAI chat completions request, got %T", result.Value)
+	}
+	return openAIRequest, nil
+}
+
+func GeminiToOpenAIRequest(geminiRequest *dto.GeminiChatRequest, info *relaycommon.RelayInfo) (*dto.GeneralOpenAIRequest, error) {
+	result, err := ConvertRequest(nil, info, types.RelayFormatOpenAI, geminiRequest)
+	if err != nil {
+		return nil, err
+	}
+	openAIRequest, ok := result.Value.(*dto.GeneralOpenAIRequest)
+	if !ok {
+		return nil, fmt.Errorf("expected OpenAI chat completions request, got %T", result.Value)
+	}
+	return openAIRequest, nil
+}