feat(pi): add pi coding agent harness (#5178) #19802

Job	Run time
Detect Version	4s
Test and Build / Test and Build	5m 12s
Check Docs Changes	0s
Migrate Dev DB	-5s
Build Dev ECR	-1s
Build ARM64 (GHCR Only)	-1s
Migrate DB / Apply Database Migrations	45s
Build AMD64 (./docker/app.Dockerfile, ghcr.io/simstudioai/simstudio, ECR_APP)	4m 5s
Build AMD64 (./docker/db.Dockerfile, ghcr.io/simstudioai/migrations, ECR_MIGRATIONS)	45s
Build AMD64 (./docker/realtime.Dockerfile, ghcr.io/simstudioai/realtime, ECR_REALTIME)	48s
Process Docs	-1s
Create GHCR Manifests	-1s
Create GitHub Release	-1s
	11m 29s

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