Update package metadata reading method in GitHub Actions workflow

[kasuken]

Refactor the method for reading package metadata in the GitHub Actions workflow to improve efficiency and clarity.

[Copilot]

Pull Request Overview

This PR refactors the GitHub Actions workflow to read package metadata using a single Node.js command instead of multiple echo statements, aiming to improve efficiency and reduce redundant file operations.

• Consolidates three separate Node.js commands into one comprehensive script
• Uses fs.appendFileSync() to write directly to GITHUB_OUTPUT instead of shell redirection
• Maintains the same output variables (version, name, vsix) for downstream workflow steps

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[Copilot]

[nitpick] This single-line command is difficult to read and maintain. Consider breaking it into multiple lines or using a here document for better readability.

Suggested change

	node -e "const fs=require('fs'); const p=require('./package.json'); const out=process.env.GITHUB_OUTPUT; fs.appendFileSync(out, `version=${p.version}\n`); fs.appendFileSync(out, `name=${p.name}\n`); fs.appendFileSync(out, `vsix=${p.name}-${p.version}.vsix\n`);"
	node <<'EOF'
	const fs = require('fs');
	const p = require('./package.json');
	const out = process.env.GITHUB_OUTPUT;
	fs.appendFileSync(out, `version=${p.version}\n`);
	fs.appendFileSync(out, `name=${p.name}\n`);
	fs.appendFileSync(out, `vsix=${p.name}-${p.version}.vsix\n`);
	EOF

[Copilot]

Missing input validation for package.json properties. If p.version or p.name contain special characters or newlines, they could corrupt the GITHUB_OUTPUT format.

Suggested change

	node -e "const fs=require('fs'); const p=require('./package.json'); const out=process.env.GITHUB_OUTPUT; fs.appendFileSync(out, `version=${p.version}\n`); fs.appendFileSync(out, `name=${p.name}\n`); fs.appendFileSync(out, `vsix=${p.name}-${p.version}.vsix\n`);"
	node -e "const fs=require('fs'); const p=require('./package.json'); const out=process.env.GITHUB_OUTPUT; const esc=s=>s.replace(/%/g,'%25').replace(/\\n/g,'%0A').replace(/\\r/g,'%0D'); fs.appendFileSync(out, `version=${esc(p.version)}\n`); fs.appendFileSync(out, `name=${esc(p.name)}\n`); fs.appendFileSync(out, `vsix=${esc(p.name)}-${esc(p.version)}.vsix\n`);"