fix(core): warn for workspace dev peer fallbacks

[puneetdixit200]

Summary

• add a dedicated peer warning when a workspace peer is only satisfied by a devDependency
• cover both requester-local devDependency fallbacks and parent workspace devDependencies
• update yarn explain peer-requirements output for the new case

Fixes #7139.

Testing

• git diff --check
• corepack yarn typecheck:all
• corepack yarn workspace @yarnpkg/cli build:cli --no-git-hash
• corepack yarn test:integration pkg-tests-specs/sources/features/peerDependenciesMeta.test.ts -t "workspace peer dependency is satisfied" --runInBand

[StantonMatt]

I took a pass at this against the current tree since it has been sitting for a bit.

On PR head debcf090, I rebuilt @yarnpkg/cli and ran the focused peerDependenciesMeta.test.ts integration file (9/9), touched-file ESLint, yarn typecheck:all, and git diff --check origin/master...HEAD.

I also merged it into current origin/master (878edb3c) in a scratch worktree, rebuilt the bundle as 4.16.0, and reran the same focused integration file (9/9), touched-file ESLint, yarn typecheck:all, and diff check. The two cases from #7139 both emit YN0093, and yarn explain peer-requirements distinguishes the requester-devDependency fallback from the parent-devDependency case.

One caveat: all visible GitHub Actions jobs are green, with only the expected big-endian skip, but the Netlify deploy-preview context is still red (state: error on deploy 6a0c7b0e8960990008e32aa5). I couldn't see public build messages for that deploy, so it likely needs a maintainer-side rerun or Netlify-side check before merge.

[clemyan]

1. There needs to be an additional criterion to trigger the new warnings: that the workspace-workspace dependency must not be dev-only
2. If a dev-dependency fallback forwards the peer request anyway, I think the "dev-only fallback" case can be handled as a "peer not provided" warning?

[puneetdixit200]

Updated in 351158b2.

What changed:

• added the @yarnpkg/cli release entry
• documented YN0093 in the error-code docs
• removed the root-workspace exception for devDependency fallback warnings
• adjusted the warning text/requester selection for devDependency fallbacks
• added acceptance coverage for root-workspace fallback and the updated warning text

Verification:

• yarn build:cli
• yarn workspace acceptance-tests test:integration pkg-tests-specs/sources/features/peerDependenciesMeta.test.ts --runInBand
• yarn typecheck:all
• PATH="$HOME/.nvm/versions/node/v22.22.3/bin:$PATH" yarn test:lint
• yarn version check
• yarn constraints
• yarn install --immutable
• git diff --check