欢迎语支持多段配置与图片

租户可配置有序文本/图片欢迎语；设置页支持增删排序与上传，Widget 空会话按序展示；兼容旧 welcome_message 字段。

server/internal/handler/settings_welcome_test.go

@@ -0,0 +1,68 @@
+package handler
+
+import (
+	"testing"
+
+	"kefu-cloud/server/internal/model"
+)
+
+func TestNormalizeWelcomeSegments(t *testing.T) {
+	SetImagePublicBase("http://localhost:9100/kefu")
+
+	_, _, err := normalizeWelcomeSegments(nil)
+	if err == nil {
+		t.Fatal("空列表应失败")
+	}
+
+	ok, first, err := normalizeWelcomeSegments([]WelcomeSegment{
+		{Type: "text", Content: "  你好  "},
+		{Type: "image", Content: "http://localhost:9100/kefu/tenants/1/welcome/a.webp"},
+		{Type: "text", Content: "请描述问题"},
+	})
+	if err != nil {
+		t.Fatalf("合法多段应通过: %v", err)
+	}
+	if len(ok) != 3 || ok[0].Content != "你好" || first != "你好" {
+		t.Fatalf("规范化结果异常: %+v first=%s", ok, first)
+	}
+
+	_, _, err = normalizeWelcomeSegments([]WelcomeSegment{
+		{Type: "image", Content: "https://evil.example/x.png"},
+	})
+	if err == nil {
+		t.Fatal("非白名单图片 URL 应失败")
+	}
+
+	tooMany := make([]WelcomeSegment, maxWelcomeSegments+1)
+	for i := range tooMany {
+		tooMany[i] = WelcomeSegment{Type: "text", Content: "x"}
+	}
+	if _, _, err := normalizeWelcomeSegments(tooMany); err == nil {
+		t.Fatal("超过段数上限应失败")
+	}
+}
+
+func TestResolveWelcomeSegmentsCompat(t *testing.T) {
+	// 仅有旧字段
+	s1 := &model.TenantSetting{WelcomeMessage: "旧欢迎语"}
+	segs := resolveWelcomeSegments(s1)
+	if len(segs) != 1 || segs[0].Type != "text" || segs[0].Content != "旧欢迎语" {
+		t.Fatalf("旧字段兼容失败: %+v", segs)
+	}
+
+	// 优先 JSON
+	s2 := &model.TenantSetting{
+		WelcomeMessage:      "旧",
+		WelcomeMessagesJSON: `[{"type":"text","content":"新1"},{"type":"image","content":"http://x/a.webp"}]`,
+	}
+	segs = resolveWelcomeSegments(s2)
+	if len(segs) != 2 || segs[0].Content != "新1" {
+		t.Fatalf("JSON 优先失败: %+v", segs)
+	}
+
+	// 空 → 默认
+	segs = resolveWelcomeSegments(&model.TenantSetting{})
+	if len(segs) != 1 || segs[0].Content != defaultWelcomeMessage {
+		t.Fatalf("默认欢迎语失败: %+v", segs)
+	}
+}