v1.4 工具集扩展 + Windows 编码攻坚

- 新增 BashTool（bash 命令执行，30s 超时 + 自愈 + 截断）
- 新增 WriteFileTool（文件写入）
- Windows GBK 编码自动转 UTF-8（golang.org/x/text）
- OpenAIProvider 新增 API 交互日志
- dumpMessages 移除截断，完整展示上下文
- cmd/claw 三段式任务演示

go.mod

@@ -3,13 +3,16 @@ module go-tiny-claw
 go 1.23.0
 
 require (
-	github.com/anthropics/anthropic-sdk-go v1.43.0 // indirect
+	github.com/anthropics/anthropic-sdk-go v1.43.0
+	github.com/openai/openai-go/v3 v3.35.0
+	golang.org/x/text v0.27.0
+)
+
+require (
 	github.com/bahlo/generic-list-go v0.2.0 // indirect
 	github.com/buger/jsonparser v1.1.2 // indirect
 	github.com/invopop/jsonschema v0.13.0 // indirect
-	github.com/joho/godotenv v1.5.1 // indirect
 	github.com/mailru/easyjson v0.7.7 // indirect
-	github.com/openai/openai-go/v3 v3.35.0 // indirect
 	github.com/standard-webhooks/standard-webhooks/libraries v0.0.1 // indirect
 	github.com/tidwall/gjson v1.18.0 // indirect
 	github.com/tidwall/match v1.1.1 // indirect