Add compute runtime sleep guard package

[rtbenfield]

Adds @prisma/compute as a publishable runtime utility package for Prisma Compute applications. The first API helps application code keep an instance awake while background work is active, without adding any CLI command surface.

Changes

• Compute package: Adds packages/compute as an ESM TypeScript library with tsdown build output, package-local verification guidance, and workspace lockfile metadata.
• Sleep guard utilities: Exposes ScaleToZeroGuard and waitUntil from packages/compute/src/index.ts. Both write paired acquire/release signals to the Prisma Compute runtime endpoint, no-op outside the runtime, and support AbortSignal as a safety bound for dangling guards.
• Consumer docs and tests: Adds README guidance for human authors and coding agents, plus tests covering signal writes, idempotent release, disposable cleanup, abort-triggered release, unavailable runtime no-op behavior, and waitUntil fire-and-forget semantics.

Why

Prisma Compute can sleep and resume applications from memory snapshots after short idle periods. Request-adjacent background work needs an explicit keep-awake signal so it is not interrupted when the request completes. The guard uses immediate one-byte writes so acquisition and release are ordered with user code, while AbortSignal.timeout(ms) lets callers bound guard lifetime if a code path does not reach release.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: ASSERTIVE

Plan: Pro

Run ID: 505e59e9-47e9-43b4-9fa6-5caa1d8135aa

📥 Commits

Reviewing files that changed from the base of the PR and between e37fe3f and 6b02c69.

📒 Files selected for processing (3)

• .github/workflows/preview-cli-package.yml
• packages/compute/src/scale-to-zero.ts
• packages/compute/tests/scale-to-zero.test.ts

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Summary by CodeRabbit

• New Features

  • Introduced @prisma/compute with utilities to keep apps awake during background work: waitUntil and ScaleToZeroGuard.

• Documentation

  • Added user-facing README and developer guidance for the new package and verification steps.

• Tests

  • Added tests covering guard acquisition/release behavior, abort handling, and waitUntil lifecycle.

• Chores

  • Added build script and package metadata for the new package; CI preview steps extended to build/test it.

Walkthrough

This PR introduces a new @prisma/compute package to the monorepo with APIs for preventing application hibernation during background work. The package includes a ScaleToZeroGuard class and waitUntil helper that write acquire/release signals to a control file, along with abort signal integration for automatic cleanup. The implementation is thoroughly tested with a Vitest suite covering guard lifecycle, promise integration, signal handling, and edge cases. Consumer documentation explains usage patterns and safety guidelines for the public APIs.

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 16.67% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title 'Add compute runtime sleep guard package' clearly summarizes the main change: introducing a new package with sleep guard utilities for Prisma Compute.
Description check	✅ Passed	The description is directly related to the changeset, explaining the purpose, implementation details, and rationale for adding the @prisma/compute package.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch feat/compute-runtime-guard

✨ Simplify code

• Create PR with simplified code
• Commit simplified code in branch feat/compute-runtime-guard

---

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[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In `@packages/compute/src/scale-to-zero.ts`:
- Around line 142-144: The current waitUntil call discards the promise returned
by Promise.resolve(promise).finally(...), which can create an unhandled
rejection; change the flow so the finally-attached promise cannot produce an
unhandled rejection — e.g., after Promise.resolve(promise).finally(() =>
guard.release()) attach a .catch(() => {}) to consume any rejection from the
finalizer chain (or otherwise capture the returned promise) so Node won’t flag
unhandled rejections; update the invocation in waitUntil where promise and
guard.release() are used.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: ASSERTIVE

Plan: Pro

Run ID: 5616e5ab-19b2-4a29-8cde-666a961beaa0

📥 Commits

Reviewing files that changed from the base of the PR and between ee7c648 and e37fe3f.

⛔ Files ignored due to path filters (1)

• pnpm-lock.yaml is excluded by !**/pnpm-lock.yaml

📒 Files selected for processing (11)

• docs/architecture/package-structure.md
• package.json
• packages/compute/AGENTS.md
• packages/compute/README.md
• packages/compute/package.json
• packages/compute/src/index.ts
• packages/compute/src/scale-to-zero-control.ts
• packages/compute/src/scale-to-zero.ts
• packages/compute/tests/scale-to-zero.test.ts
• packages/compute/tsconfig.json
• packages/compute/tsdown.config.ts

[luanvdw]

Reviewed with the local code-review. Fixed the waitUntil rejection handling, added a regression test, and made the PR workflow run compute test/build too. Local checks and CI are green.