test(tray): expand ActivityStreamService coverage with 20 new tests

Add tests covering previously untested behaviour in ActivityStreamService:
- Category defaults to "general" when null or whitespace input
- Whitespace/empty title is rejected (no-op Add)
- Insertion order (newest-first)
- GetItems maxItems limiting and zero-items edge case
- GetItems category filtering: exact match, dot-prefix sub-categories,
  case-insensitive matching, and non-match guard
- 'all' category selector returns every item
- Clear and Add both raise the Updated event
- BuildSupportBundle maxItems parameter limits output
- BuildSupportBundle includes session= and node= fields when set
- BuildSupportBundle truncates long node IDs to 16 chars + '...'
- BuildSupportBundle omits session/node fields when not provided

Total: 22 tests (was 2).

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: github-actions[bot]

tests/OpenClaw.Tray.Tests/ActivityStreamServiceTests.cs

@@ -51,4 +51,262 @@ public void BuildSupportBundle_DefaultIncludesStoredActivityWindow()
         Assert.Contains("bundle-item-399", bundle);
         Assert.Contains("bundle-item-000", bundle);
     }
+
+    // ── Add: field defaults ──
+
+    [Fact]
+    public void Add_WithAllOptionalFields_StoresFieldValues()
+    {
+        ActivityStreamService.Add(
+            "sessions",
+            "My Session",
+            details: "some detail",
+            icon: "🔥",
+            dashboardPath: "/dashboard/abc",
+            sessionKey: "sk-123",
+            nodeId: "node-xyz");
+
+        var items = ActivityStreamService.GetItems();
+
+        Assert.Single(items);
+        var item = items[0];
+        Assert.Equal("sessions", item.Category);
+        Assert.Equal("My Session", item.Title);
+        Assert.Equal("some detail", item.Details);
+        Assert.Equal("🔥", item.Icon);
+        Assert.Equal("/dashboard/abc", item.DashboardPath);
+        Assert.Equal("sk-123", item.SessionKey);
+        Assert.Equal("node-xyz", item.NodeId);
+    }
+
+    [Fact]
+    public void Add_WithNullCategory_DefaultsToGeneral()
+    {
+        ActivityStreamService.Add(null!, "Title");
+
+        var items = ActivityStreamService.GetItems();
+
+        Assert.Equal("general", items[0].Category);
+    }
+
+    [Fact]
+    public void Add_WithWhitespaceCategory_DefaultsToGeneral()
+    {
+        ActivityStreamService.Add("   ", "Title");
+
+        var items = ActivityStreamService.GetItems();
+
+        Assert.Equal("general", items[0].Category);
+    }
+
+    [Fact]
+    public void Add_WithEmptyTitle_DoesNotAddItem()
+    {
+        ActivityStreamService.Add("test", "");
+
+        var items = ActivityStreamService.GetItems();
+
+        Assert.Empty(items);
+    }
+
+    [Fact]
+    public void Add_WithWhitespaceTitle_DoesNotAddItem()
+    {
+        ActivityStreamService.Add("test", "   ");
+
+        var items = ActivityStreamService.GetItems();
+
+        Assert.Empty(items);
+    }
+
+    [Fact]
+    public void Add_StoresItemsNewestFirst()
+    {
+        ActivityStreamService.Add("test", "first");
+        ActivityStreamService.Add("test", "second");
+
+        var items = ActivityStreamService.GetItems();
+
+        Assert.Equal("second", items[0].Title);
+        Assert.Equal("first", items[1].Title);
+    }
+
+    // ── GetItems: filtering and limiting ──
+
+    [Fact]
+    public void GetItems_WithMaxItemsLessThanStored_ReturnsOnlyNewest()
+    {
+        ActivityStreamService.Add("test", "old");
+        ActivityStreamService.Add("test", "newer");
+        ActivityStreamService.Add("test", "newest");
+
+        var items = ActivityStreamService.GetItems(maxItems: 2);
+
+        Assert.Equal(2, items.Count);
+        Assert.Equal("newest", items[0].Title);
+        Assert.Equal("newer", items[1].Title);
+    }
+
+    [Fact]
+    public void GetItems_WithMaxItemsZero_ReturnsEmpty()
+    {
+        ActivityStreamService.Add("test", "item");
+
+        var items = ActivityStreamService.GetItems(maxItems: 0);
+
+        Assert.Empty(items);
+    }
+
+    [Fact]
+    public void GetItems_WithCategoryFilter_ReturnsOnlyMatchingCategory()
+    {
+        ActivityStreamService.Add("sessions", "session item");
+        ActivityStreamService.Add("nodes", "node item");
+        ActivityStreamService.Add("sessions", "another session");
+
+        var items = ActivityStreamService.GetItems(category: "sessions");
+
+        Assert.Equal(2, items.Count);
+        Assert.All(items, item => Assert.Equal("sessions", item.Category));
+    }
+
+    [Fact]
+    public void GetItems_WithCategoryAll_ReturnsEverything()
+    {
+        ActivityStreamService.Add("sessions", "s");
+        ActivityStreamService.Add("nodes", "n");
+
+        var items = ActivityStreamService.GetItems(category: "all");
+
+        Assert.Equal(2, items.Count);
+    }
+
+    [Fact]
+    public void GetItems_CategoryFilter_IsCaseInsensitive()
+    {
+        ActivityStreamService.Add("Sessions", "uppercase S");
+
+        var items = ActivityStreamService.GetItems(category: "sessions");
+
+        Assert.Single(items);
+    }
+
+    [Fact]
+    public void GetItems_CategoryFilter_MatchesDotPrefixSubcategories()
+    {
+        ActivityStreamService.Add("sessions.chat", "chat session");
+        ActivityStreamService.Add("sessions.mcp", "mcp session");
+        ActivityStreamService.Add("nodes", "unrelated");
+
+        var items = ActivityStreamService.GetItems(category: "sessions");
+
+        Assert.Equal(2, items.Count);
+        Assert.DoesNotContain(items, item => item.Category == "nodes");
+    }
+
+    [Fact]
+    public void GetItems_CategoryFilter_DoesNotMatchPartialPrefix()
+    {
+        ActivityStreamService.Add("sessionsExtra", "should not match");
+        ActivityStreamService.Add("sessions.sub", "should match");
+
+        var items = ActivityStreamService.GetItems(category: "sessions");
+
+        Assert.Single(items);
+        Assert.Equal("sessions.sub", items[0].Category);
+    }
+
+    // ── Clear ──
+
+    [Fact]
+    public void Clear_RemovesAllItems()
+    {
+        ActivityStreamService.Add("test", "item1");
+        ActivityStreamService.Add("test", "item2");
+
+        ActivityStreamService.Clear();
+
+        Assert.Empty(ActivityStreamService.GetItems());
+    }
+
+    [Fact]
+    public void Clear_RaisesUpdatedEvent()
+    {
+        var raised = false;
+        EventHandler handler = (_, _) => raised = true;
+        ActivityStreamService.Updated += handler;
+        try
+        {
+            ActivityStreamService.Clear();
+            Assert.True(raised);
+        }
+        finally
+        {
+            ActivityStreamService.Updated -= handler;
+        }
+    }
+
+    [Fact]
+    public void Add_RaisesUpdatedEvent()
+    {
+        var raised = false;
+        EventHandler handler = (_, _) => raised = true;
+        ActivityStreamService.Updated += handler;
+        try
+        {
+            ActivityStreamService.Add("test", "item");
+            Assert.True(raised);
+        }
+        finally
+        {
+            ActivityStreamService.Updated -= handler;
+        }
+    }
+
+    // ── BuildSupportBundle ──
+
+    [Fact]
+    public void BuildSupportBundle_WithMaxItemsParam_LimitsOutput()
+    {
+        for (var i = 0; i < 10; i++)
+            ActivityStreamService.Add("test", $"item-{i}");
+
+        var bundle = ActivityStreamService.BuildSupportBundle(maxItems: 3);
+
+        Assert.Contains("Items: 3", bundle);
+    }
+
+    [Fact]
+    public void BuildSupportBundle_IncludesSessionKeyAndNodeIdWhenPresent()
+    {
+        ActivityStreamService.Add("test", "title", sessionKey: "sk-abc", nodeId: "nd-xyz");
+
+        var bundle = ActivityStreamService.BuildSupportBundle();
+
+        Assert.Contains("session=sk-abc", bundle);
+        Assert.Contains("node=nd-xyz", bundle);
+    }
+
+    [Fact]
+    public void BuildSupportBundle_TruncatesLongNodeId()
+    {
+        var longNodeId = new string('a', 32);
+        ActivityStreamService.Add("test", "title", nodeId: longNodeId);
+
+        var bundle = ActivityStreamService.BuildSupportBundle();
+
+        Assert.Contains("node=" + new string('a', 16) + "...", bundle);
+        Assert.DoesNotContain("node=" + longNodeId, bundle);
+    }
+
+    [Fact]
+    public void BuildSupportBundle_OmitsSessionAndNodeFieldsWhenAbsent()
+    {
+        ActivityStreamService.Add("test", "plain item");
+
+        var bundle = ActivityStreamService.BuildSupportBundle();
+
+        Assert.DoesNotContain("session=", bundle);
+        Assert.DoesNotContain("node=", bundle);
+    }
 }