Add SSE `retry:` directive to suggest a 2-minute reconnect delay when the worker
enters idle sleep and drops silent EventSource streams. This prevents clients
from immediately reconnecting and re-waking the container, reducing unnecessary
resource usage. Update SSE encoding to support the `retry` field and add tests
for correct behavior. Improve idle disconnect logging for better observability.
move worker startup logic from server.ts to runtime.ts for better modularity
add worker-loop-policy.ts for loop control abstraction
delete legacy unit tests under tests/unit/ related to compute worker and control-plane
add vitest config and test directories for compute-core and compute-worker
add vitest workflow for CI
update package.json scripts for new test commands and add vitest as dev dependency
BREAKING CHANGE: worker entrypoint is now compute/worker/src/runtime.ts instead of server.ts; legacy Playwright-based unit tests for compute worker are removed in favor of Vitest
