fix(test-utils): bump waitFor default timeout to 10s

Under full `just test-all` load the Phoenix socket can take a beat to
propagate a new subscription's filter to the backend before a mutation
fires, so R-01 occasionally timed out at 5s. Passing runs still resolve
instantly on event arrival — this only widens the flake window.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

packages/test-utils/src/realtime-helpers.ts

@@ -73,7 +73,10 @@ export async function subscribePostgresChanges<T = Record<string, unknown>>(
 
 	function waitFor(
 		predicate: (e: { eventType: string; new: T; old: T | null }) => boolean,
-		timeoutMs = 5_000
+		// 10s default: under load (full `just test-all`), the Phoenix socket can take
+		// a beat to propagate a fresh subscription's filter before the mutation fires.
+		// Passing runs resolve immediately on event arrival — this only bounds the flake.
+		timeoutMs = 10_000
 	) {
 		const existing = events.find(predicate);
 		if (existing) return Promise.resolve(existing);