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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[github-actions]

📦 Binary Size-limit

Comparing 7c4bf4b to perf: disable output.pathinfo by default (#12306) by neverland

❌ Size increased by 8.00KB from 47.67MB to 47.68MB (⬆️0.02%)

[codspeed-hq]

CodSpeed Performance Report

Merging #12226 will not alter performance

_{Comparing fix/use-shorthand-require (7c4bf4b) with main (4322519)}

Summary

✅ 17 untouched

[chenjiahan]

LGTM 👍