sync: bring over remaining release/custom-0.1.115 changes

- Extract PublicSettingsInjectionPayload named struct with drift test
- Add channel_monitor_default_interval_seconds to SSR injection
- Add image_output_price to SupportedModelChip
- Simplify AppSidebar buildSelfNavItems (admins see available channels)
- Add gateway WARN logs for 503 no-available-accounts branches
- Wire ChannelMonitorRunner into provideCleanup for graceful shutdown
- Add migrations 130/131 (CC template userid fix + mimicry field cleanup)
- Clean up fork-only features (sora, claude max simulation, client affinity)
- Remove ~320 obsolete i18n keys
- Add codexUsage utility, WechatServiceButton, BulkEditAccountModal
- Tidy go.sum

backend/internal/service/openai_codex_transform.go

@@ -187,13 +187,9 @@ func applyCodexOAuthTransform(reqBody map[string]any, isCodexCLI bool, isCompact
 }
 
 func normalizeCodexModel(model string) string {
-	model = strings.TrimSpace(model)
 	if model == "" {
 		return "gpt-5.4"
 	}
-	if isOpenAIImageGenerationModel(model) {
-		return model
-	}
 
 	modelID := model
 	if strings.Contains(modelID, "/") {
@@ -235,78 +231,6 @@ func normalizeCodexModel(model string) string {
 	return "gpt-5.4"
 }
 
-func hasOpenAIImageGenerationTool(reqBody map[string]any) bool {
-	rawTools, ok := reqBody["tools"]
-	if !ok || rawTools == nil {
-		return false
-	}
-	tools, ok := rawTools.([]any)
-	if !ok {
-		return false
-	}
-	for _, rawTool := range tools {
-		toolMap, ok := rawTool.(map[string]any)
-		if !ok {
-			continue
-		}
-		if strings.TrimSpace(firstNonEmptyString(toolMap["type"])) == "image_generation" {
-			return true
-		}
-	}
-	return false
-}
-
-func normalizeOpenAIResponsesImageGenerationTools(reqBody map[string]any) bool {
-	rawTools, ok := reqBody["tools"]
-	if !ok || rawTools == nil {
-		return false
-	}
-	tools, ok := rawTools.([]any)
-	if !ok {
-		return false
-	}
-
-	modified := false
-	for _, rawTool := range tools {
-		toolMap, ok := rawTool.(map[string]any)
-		if !ok || strings.TrimSpace(firstNonEmptyString(toolMap["type"])) != "image_generation" {
-			continue
-		}
-		if _, ok := toolMap["output_format"]; !ok {
-			if value := strings.TrimSpace(firstNonEmptyString(toolMap["format"])); value != "" {
-				toolMap["output_format"] = value
-				modified = true
-			}
-		}
-		if _, ok := toolMap["output_compression"]; !ok {
-			if value, exists := toolMap["compression"]; exists && value != nil {
-				toolMap["output_compression"] = value
-				modified = true
-			}
-		}
-		if _, ok := toolMap["format"]; ok {
-			delete(toolMap, "format")
-			modified = true
-		}
-		if _, ok := toolMap["compression"]; ok {
-			delete(toolMap, "compression")
-			modified = true
-		}
-	}
-	return modified
-}
-
-func validateOpenAIResponsesImageModel(reqBody map[string]any, model string) error {
-	if !hasOpenAIImageGenerationTool(reqBody) {
-		return nil
-	}
-	model = strings.TrimSpace(model)
-	if !isOpenAIImageGenerationModel(model) {
-		return nil
-	}
-	return fmt.Errorf("/v1/responses image_generation requests require a Responses-capable text model; image-only model %q is not allowed", model)
-}
-
 func normalizeOpenAIModelForUpstream(account *Account, model string) string {
 	if account == nil || account.Type == AccountTypeOAuth {
 		return normalizeCodexModel(model)