Add ToolRenderResult interface for custom tool rendering

- Changed ToolRenderer return type from TemplateResult to ToolRenderResult
- ToolRenderResult = { content: TemplateResult, isCustom: boolean }
- isCustom: true = no card wrapper, false = wrap in card
- Updated all existing tool renderers to return new format
- Updated Messages.ts to handle custom rendering

This enables tools to render without default card chrome when needed.

packages/web-ui/src/components/Messages.ts

@@ -231,16 +231,22 @@ export class ToolMessage extends LitElement {
 		const result: ToolResultMessageType<any> | undefined = this.aborted
 			? { role: "toolResult", isError: true, output: "", toolCallId: this.toolCall.id, toolName: this.toolCall.name }
 			: this.result;
-		const toolContent = renderTool(
+		const renderResult = renderTool(
 			toolName,
 			this.toolCall.arguments,
 			result,
 			!this.aborted && (this.isStreaming || this.pending),
 		);
 
+		// Handle custom rendering (no card wrapper)
+		if (renderResult.isCustom) {
+			return renderResult.content;
+		}
+
+		// Default: wrap in card
 		return html`
 			<div class="p-2.5 border border-border rounded-md bg-card text-card-foreground shadow-xs">
-				${toolContent}
+				${renderResult.content}
 			</div>
 		`;
 	}