fix: a2ui is much closer to bDS parity than before

test/bds/desktop/shell_live/chat_editor/tool_surfaces_test.exs

@@ -0,0 +1,60 @@
+defmodule BDS.Desktop.ShellLive.ChatEditor.ToolSurfacesTest do
+  use ExUnit.Case, async: true
+
+  alias BDS.Desktop.ShellLive.ChatEditor.ToolSurfaces
+
+  describe "build_render_surface/3 for render_chart" do
+    test "reads chartType in camelCase (as LLM sends it)" do
+      tool_call = %{
+        name: "render_chart",
+        arguments: %{
+          "chartType" => "heatmap",
+          "title" => "Posts per Month",
+          "series" => [
+            %{"label" => "2024", "value" => 0, "segments" => [
+              %{"label" => "Jan", "value" => 5},
+              %{"label" => "Feb", "value" => 8}
+            ]}
+          ]
+        }
+      }
+
+      surface = ToolSurfaces.build_render_surface(tool_call, "test-heatmap-0", %{})
+      assert surface.type == "chart"
+      assert surface.chart_type == "heatmap"
+    end
+
+    test "reads chart_type in snake_case (legacy form)" do
+      tool_call = %{
+        name: "render_chart",
+        arguments: %{"chart_type" => "pie", "series" => []}
+      }
+
+      surface = ToolSurfaces.build_render_surface(tool_call, "test-pie-0", %{})
+      assert surface.chart_type == "pie"
+    end
+
+    test "defaults to bar when chartType field is missing" do
+      tool_call = %{
+        name: "render_chart",
+        arguments: %{"title" => "No type", "series" => []}
+      }
+
+      surface = ToolSurfaces.build_render_surface(tool_call, "test-bar-0", %{})
+      assert surface.chart_type == "bar"
+    end
+
+    test "handles all chart types via camelCase" do
+      for chart_type <- ["bar", "stacked-bar", "line", "area", "pie", "donut", "heatmap"] do
+        tool_call = %{
+          name: "render_chart",
+          arguments: %{"chartType" => chart_type, "series" => []}
+        }
+
+        surface = ToolSurfaces.build_render_surface(tool_call, "test-#{chart_type}-0", %{})
+        assert surface.chart_type == chart_type,
+          "Expected chart_type #{inspect(chart_type)}, got #{inspect(surface.chart_type)}"
+      end
+    end
+  end
+end