chore: 初始开源发布

iotlcm-bot：独立飞书应用机器人（读取 Worker 终态 Run JSON，渲染并发送全量同步结果卡片）。

- Go module：git.5iot.com/iotlcm/iotlcm-bot → git.5iot.com/iotlcm-public/iotlcm-bot
- 飞书凭据占位：appId/appSecret/chatId → ${FEISHU_APP_ID}/${FEISHU_APP_SECRET}/${FEISHU_CHAT_ID}
- 移除内部资产：CI 触发器
- Dockerfile 改用公共基础镜像（golang:1.25-alpine → scratch）
- README 重写（命令/配置/挂载契约/常见问题），去掉内部环境路径
- 补 Apache-2.0 LICENSE，LF 行尾 + .gitattributes

internal/feishu/client_test.go

@@ -0,0 +1,62 @@
+package feishu
+
+import (
+	"context"
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+)
+
+func TestSendText(t *testing.T) {
+	var gotText string
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		switch r.URL.Path {
+		case "/open-apis/auth/v3/tenant_access_token/internal":
+			_, _ = w.Write([]byte(`{"code":0,"tenant_access_token":"test-token","expire":7200}`))
+		case "/open-apis/im/v1/messages":
+			if r.URL.Query().Get("receive_id_type") != "chat_id" || r.Header.Get("Authorization") != "Bearer test-token" {
+				t.Errorf("unexpected request: %s %s", r.URL.String(), r.Header.Get("Authorization"))
+			}
+			var payload struct {
+				ReceiveID string `json:"receive_id"`
+				MsgType   string `json:"msg_type"`
+				Content   string `json:"content"`
+			}
+			if err := json.NewDecoder(r.Body).Decode(&payload); err != nil {
+				t.Error(err)
+			}
+			if payload.ReceiveID != "test-chat" || payload.MsgType != "text" {
+				t.Errorf("unexpected payload: %+v", payload)
+			}
+			var content struct {
+				Text string `json:"text"`
+			}
+			if err := json.Unmarshal([]byte(payload.Content), &content); err != nil {
+				t.Error(err)
+			}
+			gotText = content.Text
+			_, _ = w.Write([]byte(`{"code":0,"msg":"success"}`))
+		default:
+			http.NotFound(w, r)
+		}
+	}))
+	defer server.Close()
+	client := NewClient("test-app", "test-secret", "test-chat")
+	client.baseURL = server.URL
+	message := "连接测试：含引号 \" 和换行\n第二行"
+	if err := client.SendText(context.Background(), message); err != nil {
+		t.Fatal(err)
+	}
+	if gotText != message {
+		t.Fatalf("text mismatch: %q", gotText)
+	}
+}
+
+func TestSendTextRejectsEmpty(t *testing.T) {
+	client := NewClient("test-app", "test-secret", "test-chat")
+	if err := client.SendText(context.Background(), ""); err == nil || !strings.Contains(err.Error(), "text is required") {
+		t.Fatalf("unexpected error: %v", err)
+	}
+}