[Task 14] Scheduler + immediate first run

[lubobill1990]

Task 14 — Scheduler + immediate first run

Depends on: 13
Unblocks: 15

Goal

Background scheduler that runs runPricingSync() once at startup and then
every --pricing-sync-interval-days days.

Scope

New file src/lib/pricing-scheduler.ts:

export function schedulePricingSync(intervalDays: number): void

Implementation:

const intervalMs = intervalDays * 86_400_000
function tick() {
  const last = readMeta('last_pricing_sync_ts') ?? 0
  const delay = Math.max(0, last + intervalMs - Date.now())
  setTimeout(async () => {
    try { await runPricingSync({}) }
    catch (e) { consola.warn('Pricing sync failed:', e) }
    tick()
  }, delay)
}
tick()

Wire it from src/start.ts AFTER serve(...):

if (!options.pricingSyncDisabled) {
  schedulePricingSync(options.pricingSyncIntervalDays)
}

Add CLI flags:

• --pricing-sync-model <id> (default gpt-5.4)
• --pricing-sync-interval-days <n> (default 7)
• --pricing-sync-disabled (default false)

Definition of Done

• Booting a fresh DB triggers a sync within seconds (or fails gracefully
  if accounts/network unavailable).
• Booting with last_pricing_sync_ts = now - 1 day waits 6 days.
• Booting with last_pricing_sync_ts = now - 8 days syncs immediately.
• --pricing-sync-disabled skips scheduling entirely.
• Scheduler errors do NOT crash the proxy.

---

• Source: docs/tasks/14-pricing-scheduler.md
• Design: docs/design/
• Phase: pricing
• Depends on tasks: 13