Fix abort detection to use message stopReason instead of global isStreaming

When abort happens during tool call streaming, the tool result should show as aborted.
Previously used global isStreaming state which would flip when new messages streamed in,
causing spinner to reappear incorrectly.

Changes:
- Use message.stopReason === "aborted" to detect aborted tool calls
- Create synthetic error result for aborted tool calls in ToolMessage component
- Fix Ollama provider key test to return true (can't know which model to test)
- Add newline before HTML execution logs in artifacts update

packages/web-ui/src/tools/artifacts/artifacts.ts

@@ -449,7 +449,7 @@ export class ArtifactsPanel extends LitElement {
 		let result = `Updated file ${params.filename}`;
 		if (this.getFileType(params.filename) === "html" && !options.skipWait) {
 			const logs = await this.waitForHtmlExecution(params.filename);
-			result += logs;
+			result += `\n${logs}`;
 		}
 
 		return result;