Emails workspace admins at 50/75/100% of Compute spend budget. ENG-2869 stored the settings. This PR reads them and sends alerts. Enforcement (stopping compute at 100%) is ENG-2923. deploy_spend_budget_stop is carried through and only logged here.

A deploy-spend-check cron fires CronService.RunDeploySpendCheck. Local dev runs every minute (dev/k8s/charts/restate-cronjobs/values.yaml). Production cadence (15 minutes) lands in the infra repo.

The orchestrator lists workspaces with a budget, prices month-to-date usage from one grouped ClickHouse scan, computes overage = max(0, gross − included credit), and fans out DeploySpendCheckService.CheckWorkspaceSpend for workspaces at or past the lowest alert threshold. Included credit comes from deploy_included_credit_cents (dashboard webhook on invoice.payment_succeeded).

Also adds dashboard deployPricing.ts, deployCredits tests, and orchestrator integration coverage. The full suspend/resume integration test (deploy_spend_check_test) needs DeployTeardownService and lands on ENG-2923 (#6542), not this PR.

Closes ENG-2904. Stacked on ENG-2908 (#6456).

Local setup

mise run dev
stripe login

Optional alert emails: dev/.env.workos, dev/.env.resend.

stripe listen --forward-to http://localhost:3000/api/webhooks/stripe

Test plan

mise exec -- bazel test //svc/ctrl/worker/cron/deployspendcheck:deployspendcheck_test
mise exec -- bazel test //svc/ctrl/worker/cron:cron_test --test_filter=RunDeploySpendCheck
mise exec -- pnpm --dir=web/apps/dashboard vitest run lib/stripe/deployCredits.test.ts lib/stripe/deployPricing.test.ts
mise exec -- bazel build --nobuild //svc/ctrl/worker/cron:cron //svc/ctrl/worker/cron/deployspendcheck:deployspendcheck

Trigger spend check without waiting for cron:

curl -X POST "http://localhost:8080/hydra.v1.CronService/$(date -u +%Y-%m)/RunDeploySpendCheck/send"

End-to-end: subscribe to Deploy, set a spend budget, drive usage past 50% beyond included credit, wait ~1 minute or curl above, confirm alert email if Resend/WorkOS configured.

mise run unkey -- dev stripe grants --customer cus_...