feat(eve): external cron mode for self-hosted builds (EVE_EXTERNAL_CRON=1)

[warmwind]

Closes #707

Problem

Self-hosted (node preset) builds fire schedules from Nitro's in-process runner with no off switch: N replicas fire every schedule N times, ticks that land while the process is down are silently lost, and production exposes no dispatch endpoint — so a hosting platform can neither pause a schedule nor trigger one manually, and the container must stay always-on just to keep the clock. None of this applies on Vercel, where the platform owns the clock through the unguessable token cron route.

Change

Building with EVE_EXTERNAL_CRON=1 (node preset, production only — no effect on Vercel builds or eve dev):

• No in-process cron. registerScheduleTaskHandlers gains registerCronSchedules: false: task handlers are registered as before, but nothing is written to scheduledTasks, so startScheduleRunner in the node-server entry no-ops.
• Token cron route on the node preset. The build mounts POST /eve/v1/cron/<token> (reusing createEveCronHandlerRoute). The handler mirrors Nitro's Vercel cron handler contract — the due cron expression arrives in x-vercel-cron-schedule, and a configured CRON_SECRET is enforced as a bearer token with a timing-safe compare — and dispatches every schedule registered for that expression through dispatchScheduleTask (registrations are baked into the virtual handler, since scheduledTasks is deliberately empty in this mode).
• Cron manifest in build output. compiled writes .output/eve/cron-manifest.json with the route path and one entry per distinct cron expression, each listing the schedules it dispatches — the self-hosted equivalent of the config.crons[] Vercel reads from build output. The path is the credential, so the manifest lives only in build output (readable by whoever ran the build) and is never served.

An external scheduler then drives the deployment exactly like Vercel Cron does: on each due tick, POST the route with the cron expression in the header. Keeping the request contract identical means one scheduler client works against both Vercel and self-hosted deployments.

Testing

• Unit: registerCronSchedules: false registers tasks/virtual modules with scheduledTasks left empty; route registration bakes in the schedule map at an unguessable path; isExternalCronEnabled parsing; handler tests for dispatch-by-expression, empty match, missing header (400), and CRON_SECRET enforcement (401/200).
• Integration: the compiled hook writes the expected manifest JSON into the output directory.
• pnpm test:unit (4439), pnpm test:integration (386), package typecheck, lint, guard:invariants, docs:check all pass.

🤖 Generated with Claude Code

https://claude.ai/code/session_0164WUaSv9mN58wgnnoN2vKG

[vercel]

@warmwind is attempting to deploy a commit to the Vercel Team on Vercel.

A member of the Team first needs to authorize it.