Blocks: Declare the @types/react-is devDependency

[manzoorwanijk]

What?

Follow up to #81148. Declares @types/react-is as a devDependency of @wordpress/blocks.

Why?

packages/blocks imports react-is but only packages/plugins declares @types/react-is. Default npm hoisting puts it in the root node_modules, so tsc finds it by accident. Without hoisting it fails:

packages/blocks/src/store/process-block-type.ts(6,36): error TS7016: Could not find a declaration file for module 'react-is'.

Same failure on #75814: https://github.com/WordPress/gutenberg/actions/runs/30979264622/job/92219984529?pr=75814

How?

devDependencies, not dependencies: isValidElementType returns a boolean, so no react-is type reaches build-types.

Testing Instructions

npx tsc --build packages/blocks/tsconfig.json passes. To see the original failure, run npm install --install-strategy=linked on trunk first.

Use of AI Tools

Authored with Claude Code. I have reviewed and take responsibility for the changes.

[github-actions]

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Co-authored-by: manzoorwanijk <manzoorwanijk@git.wordpress.org>
Co-authored-by: Mamaduka <mamaduka@git.wordpress.org>

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[Mamaduka]

Thanks, @manzoorwanijk!

[github-actions]

Size Change: -138 B (0%)

Total Size: 7.81 MB

📦 View Changed

Filename	Size	Change
build/styles/edit-widgets/style-rtl.css	5.04 kB	-36 B (-0.71%)
build/styles/edit-widgets/style-rtl.min.css	3.61 kB	-32 B (-0.88%)
build/styles/edit-widgets/style.css	5.03 kB	-37 B (-0.73%)
build/styles/edit-widgets/style.min.css	3.61 kB	-33 B (-0.91%)

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[github-actions]

Flaky tests detected in 4eea775.
Some tests passed with failed attempts. The failures may not be related to this commit but are still reported for visibility. See the documentation for more information.

🔍 Workflow run URL: https://github.com/WordPress/gutenberg/actions/runs/30980501785
📝 Reported issues:

• [Flaky Test] should partially select text from block to block in either direction #80835 in /test/e2e/specs/editor/various/multi-block-selection.spec.js
• [Flaky Test] two users concurrently move list items (RTC WebSocket) #79951 in /test/e2e/specs/editor/collaboration/collaboration-stress.spec.ts