[flags] Preserve serving mode when flag rules change

[chriswdmr]

• Preserve an environment’s serving mode when flag rules are added, updated, moved, or removed
• Add a shared warning when rule edits are saved while an environment is still serving a fixed variant
• Update CLI rule command tests to cover the warning and the paused-environment behavior

[changeset-bot]

🦋 Changeset detected

Latest commit: d1eb885

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
vercel	Patch

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[github-actions]

🧪 Unit Test Strategy

Comparing: 4998ec8 → d1eb885 (view diff)

Strategy: Affected packages only

✅ Only testing packages that have been modified or depend on modified packages.

Affected packages - 1 (2%)

1. vercel

Unaffected packages - 48 (98%)

1. @vercel-internals/get-package-json
2. @vercel-internals/ipc-proxy
3. @vercel/aws
4. @vercel/backends
5. @vercel/build-utils
6. @vercel/cervel
7. @vercel/cli-auth
8. @vercel/cli-config
9. @vercel/cli-exec
10. @vercel/client
11. @vercel/config
12. @vercel/connect
13. @vercel/container
14. @vercel/detect-agent
15. @vercel/edge
16. @vercel/elysia
17. @vercel/error-utils
18. @vercel/express
19. @vercel/fastify
20. @vercel/firewall
21. @vercel/frameworks
22. @vercel/fs-detectors
23. @vercel/functions
24. @vercel/gatsby-plugin-vercel-analytics
25. @vercel/gatsby-plugin-vercel-builder
26. @vercel/go
27. @vercel/h3
28. @vercel/hono
29. @vercel/hydrogen
30. @vercel/koa
31. @vercel/nestjs
32. @vercel/next
33. @vercel/node
34. @vercel/oidc
35. @vercel/oidc-aws-credentials-provider
36. @vercel/passport
37. @vercel/python
38. @vercel/python-analysis
39. @vercel/redwood
40. @vercel/related-projects
41. @vercel/remix-builder
42. @vercel/routing-utils
43. @vercel/ruby
44. @vercel/rust
45. @vercel/static-build
46. @vercel/static-config
47. @vercel/vc-native
48. examples

Results

• Unit tests: Only affected packages will run unit tests
• E2E tests: Running in parallel in this workflow
• Type checks: Only affected packages will run type checks

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This comment is automatically generated based on the affected testing strategy

[vincent-derks]

One comment from cursor regarding the warning. Not a blocker for me, but maybe you could still fix it

[github-actions]

📦 CLI Tarball Ready

The Vercel CLI tarball for this PR is now available!

Quick Test

You can test this PR's CLI directly by running:

npx https://vercel-gj1fzn3oi.vercel.sh/tarballs/vercel.tgz --help

Use in vercel.json

To use this CLI version in your project builds, add to your vercel.json:

{
  "build": {
    "env": {
      "VERCEL_CLI_VERSION": "vercel@https://vercel-gj1fzn3oi.vercel.sh/tarballs/vercel.tgz"
    }
  }
}

Python Runtime Wheel

A vercel-runtime wheel was also built for this PR.
To use in your Python project builds, also set this environment variable:

VERCEL_RUNTIME_PYTHON="vercel-runtime @ https://vercel-gj1fzn3oi.vercel.sh/tarballs/vercel_runtime-0.17.0.dev1783948033+d1eb885-py3-none-any.whl"

Python Workers Wheel

A vercel-workers wheel was also built for this PR.
To use in your Python project builds, also set this environment variable:

VERCEL_WORKERS_PYTHON="vercel-workers @ https://vercel-gj1fzn3oi.vercel.sh/tarballs/vercel_workers-0.1.0.dev1783948033+d1eb885-py3-none-any.whl"

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This comment is automatically generated