chore: update Node.js versions in CI workflows

[Aias00]

No description provided.

[Copilot]

Pull request overview

This PR updates Node.js versions across CI workflows and standardizes the package manager to npm. The changes remove EOL Node.js 12.x from the test matrix, update the sync workflow to use Node.js 20, and correct an inconsistency where the deploy workflow was using yarn instead of npm.

Changes:

• Updated Node.js version from 16 to 20 in the sync-to-main workflow
• Standardized package manager from yarn to npm in the deploy workflow
• Removed EOL Node.js 12.x from the build test matrix

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
.github/workflows/sync-to-main.yml	Updates Node.js version from 16 to 20 for the sync workflow
.github/workflows/deploy.yml	Corrects package manager from yarn to npm, aligning with project standards
.github/workflows/build.yml	Removes EOL Node.js 12.x from the test matrix

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[Copilot]

The PR title indicates "update Node.js versions in CI workflows," but this change switches the package manager from yarn to npm. While this change appears correct (the project uses npm with package-lock.json and has no yarn.lock), it represents a different type of change than what the PR title suggests. Consider updating the PR title or description to reflect that both Node.js version updates and package manager standardization are included in this PR.