feat: support shorthand function for module factory to reduce bundle size

[JSerFeng]

Summary

Introducing new output.environment.methodShorthand. If target environment support this, module factories will be rendered as object method shorthand form.

Before

__webapck_modules__ = {
  "./src/app.ts": function() {}
}

This PR:

__webpack_modules__ = {
"./src/app.ts"() {}
}

Related links

Checklist

• Tests updated (or not required).
• Documentation updated (or not required).

[Copilot]

Pull Request Overview

This PR introduces support for ES2015 object method shorthand syntax in module factory definitions to reduce bundle size. When the target environment supports this feature, module factories are rendered using shorthand notation instead of the traditional function property syntax.

Key Changes

• Module factories now use shorthand syntax ("./src/app.ts"() {}) instead of traditional function properties ("./src/app.ts": function() {})
• This optimization reduces bundle size by eliminating the : function portion of each module factory definition

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[netlify]

✅ Deploy Preview for rspack canceled.

Name	Link
🔨 Latest commit	4dae46c
🔍 Latest deploy log	https://app.netlify.com/projects/rspack/deploys/691d4421b02e610008a4ee7f

[github-actions]

📦 Binary Size-limit

Comparing 4dae46c to fix: should inject prefetch startup in entry chunk instead of runtime chunk (#12233) by harpsealjs

❌ Size increased by 1.00KB from 47.48MB to 47.48MB (⬆️0.00%)

[codspeed-hq]

CodSpeed Performance Report

Merging #12226 will not alter performance

_{Comparing fix/use-shorthand-require (4dae46c) with main (0b8a3bb)}

Summary

✅ 17 untouched