Embed SvelteKit static build in Go binary via go:embed. Event bus
for pub/sub with deploy log, instance status, and deploy status events.
SSE endpoints for real-time streaming. Frontend SSE client with
exponential backoff reconnection. Makefile for build pipeline.
Update Phase 12 auth plan with OAuth2/OIDC support.
Create structured plan files with 12 phases covering the full
implementation: scaffold, store, crypto, Docker/NPM clients,
registry poller, webhook, deployer, API layer, SvelteKit frontend,
embedding, and hardening.