Bump the npm-dependencies group across 1 directory with 3 updates

Bumps the npm-dependencies group with 3 updates in the / directory: [phaser](https://github.com/phaserjs/phaser), [postcss](https://github.com/postcss/postcss) and [esbuild](https://github.com/evanw/esbuild).


Updates `phaser` from 3.90.0 to 4.0.0
- [Release notes](https://github.com/phaserjs/phaser/releases)
- [Changelog](https://github.com/phaserjs/phaser/blob/master/CHANGELOG.md)
- [Commits](phaserjs/phaser@v3.90.0...v4.0.0)

Updates `postcss` from 8.5.8 to 8.5.9
- [Release notes](https://github.com/postcss/postcss/releases)
- [Changelog](https://github.com/postcss/postcss/blob/main/CHANGELOG.md)
- [Commits](postcss/postcss@8.5.8...8.5.9)

Updates `esbuild` from 0.25.12 to 0.28.0
- [Release notes](https://github.com/evanw/esbuild/releases)
- [Changelog](https://github.com/evanw/esbuild/blob/main/CHANGELOG-2025.md)
- [Commits](evanw/esbuild@v0.25.12...v0.28.0)

---
updated-dependencies:
- dependency-name: phaser
  dependency-version: 4.0.0
  dependency-type: direct:production
  update-type: version-update:semver-major
  dependency-group: npm-dependencies
- dependency-name: postcss
  dependency-version: 8.5.9
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: npm-dependencies
- dependency-name: esbuild
  dependency-version: 0.28.0
  dependency-type: direct:development
  update-type: version-update:semver-minor
  dependency-group: npm-dependencies
...

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Author: dependabot[bot]