refactor: rebrand from cs-agent to BossChat

- Rename Go module: cs-agent → bosschat
- Rename all import paths across 200+ Go files
- Rename SDK: cs-ai-agent-sdk → bosschat-sdk
- Rename message protocol: cs-agent:* → bosschat:*
- Rename JS globals: CSAgentConfig → BossChatConfig
- Rename CSS classes: cs-agent-* → bosschat-*
- Update Makefile APP_NAME and ARCHIVE_NAME
- Update logo assets
- Fix display name: BoosChat → BossChat

cmd/testdata/kb/kb.go

@@ -2,10 +2,10 @@ package kb
 
 import (
 	"bytes"
-	"cs-agent/internal/models"
-	"cs-agent/internal/pkg/constants"
-	"cs-agent/internal/pkg/enums"
-	"cs-agent/internal/repositories"
+	"bosschat/internal/models"
+	"bosschat/internal/pkg/constants"
+	"bosschat/internal/pkg/enums"
+	"bosschat/internal/repositories"
 	"encoding/json"
 	"fmt"
 	"os"
@@ -152,10 +152,10 @@ func ensureKnowledgeBase(db *gorm.DB) (*models.KnowledgeBase, error) {
 
 func ensureFAQKnowledgeBase(db *gorm.DB) (*models.KnowledgeBase, error) {
 	now := time.Now()
-	item := repositories.KnowledgeBaseRepository.FindOne(db, sqls.NewCnd().Eq("name", "BoosChat 客服平台 FAQ"))
+	item := repositories.KnowledgeBaseRepository.FindOne(db, sqls.NewCnd().Eq("name", "BossChat 客服平台 FAQ"))
 	if item == nil {
 		item = &models.KnowledgeBase{
-			Name:                  "BoosChat 客服平台 FAQ",
+			Name:                  "BossChat 客服平台 FAQ",
 			Description:           "模拟真实客服场景的 FAQ 测试数据，覆盖账号、坐席、机器人、知识库、工单、计费与发票等常见问题。",
 			KnowledgeType:         string(enums.KnowledgeBaseTypeFAQ),
 			Status:                enums.StatusOk,