webui: make tool call failures less "error"-y

It's unnecessarily red/jarring.
This now matches the termui.

Co-Authored-By: sketch <hello@sketch.dev>
diff --git a/webui/src/web-components/sketch-tool-card.ts b/webui/src/web-components/sketch-tool-card.ts
index 35843f7..c90c55d 100644
--- a/webui/src/web-components/sketch-tool-card.ts
+++ b/webui/src/web-components/sketch-tool-card.ts
@@ -197,7 +197,7 @@
   render() {
     const toolCallStatus = this.toolCall?.result_message
       ? this.toolCall?.result_message.tool_error
-        ? html`❌
+        ? html`🙈
             <span class="tool-error-message"
               >${this.toolCall?.result_message.tool_result}</span
             >`