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/quickreply/init.go

@@ -1,9 +1,9 @@
 package quickreply
 
 import (
-	"cs-agent/internal/models"
-	"cs-agent/internal/pkg/enums"
-	"cs-agent/internal/repositories"
+	"bosschat/internal/models"
+	"bosschat/internal/pkg/enums"
+	"bosschat/internal/repositories"
 	"time"
 
 	"github.com/mlogclub/simple/sqls"
@@ -22,7 +22,7 @@ func Init() error {
 			id:        1,
 			groupName: "新客接待",
 			title:     "首次接入欢迎语",
-			content:   "您好，欢迎来到 BoosChat 客服中心，我是今天为您服务的顾问。您可以直接告诉我您想了解的产品、价格或接入方式，我这边先帮您快速判断。",
+			content:   "您好，欢迎来到 BossChat 客服中心，我是今天为您服务的顾问。您可以直接告诉我您想了解的产品、价格或接入方式，我这边先帮您快速判断。",
 			status:    enums.StatusOk,
 			sortNo:    100,
 		},