feat: add pi-condense with default enablement

extensions/condense.ts

@@ -0,0 +1,12 @@
+import { getAgentDir, type ExtensionAPI } from "@earendil-works/pi-coding-agent";
+import { ensureCondenseEnabledDefault } from "./condense-config.ts";
+
+/** Apply the bundle default before pi-condense reads settings on session_start. */
+export default async function bundledCondenseExtension(pi: ExtensionAPI): Promise<void> {
+	const result = ensureCondenseEnabledDefault(getAgentDir());
+	if (result === "skipped-invalid") {
+		console.warn("my-pi: skipped the pi-condense default because settings.json or contextPrune is invalid");
+	}
+	const { default: condenseExtension } = await import("../node_modules/pi-condense/index.ts");
+	condenseExtension(pi);
+}