refactor(landing): DRY page metadata via buildLandingMetadata + deriv… #20430

Job	Run time
Detect Version	3s
Test and Build / Test and Build	5m 42s
Migrate Dev DB	-1s
Check Docs Changes	-8s
Build ARM64 (GHCR Only)	0s
Build Dev ECR	0s
Migrate DB / Apply Database Migrations	39s
Build AMD64 (./docker/app.Dockerfile, ghcr.io/simstudioai/simstudio, ECR_APP)	3m 14s
Build AMD64 (./docker/realtime.Dockerfile, ghcr.io/simstudioai/realtime, ECR_REALTIME)	53s
Build AMD64 (./docker/db.Dockerfile, ghcr.io/simstudioai/migrations, ECR_MIGRATIONS)	52s
Build AMD64 (./docker/pii.Dockerfile, ghcr.io/simstudioai/pii, ECR_PII)	26s
Create GHCR Manifests	0s
Process Docs	0s
Create GitHub Release	0s
	11m 40s

Provide feedback