fix(navbar): eliminate auth button flash using useSyncExternalStore (… #14449

Job	Run time
Detect Version	4s
Test and Build / Test and Build	46s
Check Docs Changes	0s
Build AMD64 (./docker/db.Dockerfile, ghcr.io/simstudioai/migrations, ECR_MIGRATIONS)	1m 32s
Build AMD64 (./docker/realtime.Dockerfile, ghcr.io/simstudioai/realtime, ECR_REALTIME)	1m 49s
Build AMD64 (./docker/app.Dockerfile, ghcr.io/simstudioai/simstudio, ECR_APP)	5m 32s
Build ARM64 (GHCR Only)	0s
Create GitHub Release	-1s
Create GHCR Manifests	-1s
Process Docs	-1s
	9m 40s

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