chore: add EditorConfig, Nix flake, and update dependencies

[farhnkrnapratma]

Changes

• Add EditorConfig for consistent code formatting
• Add Nix flake for reproducible dev environment
• Update dependencies (Astro v5.16.10, Starlight v0.37.3)
• Prepare Indonesian docs directory structure

[Copilot]

Pull request overview

This PR introduces development tooling improvements and updates core dependencies for the AerynOS documentation site. It adds EditorConfig for consistent code formatting across editors, establishes a Nix flake for reproducible development environments, updates Astro to v5.16.10 and Starlight to v0.37.3, and creates the directory structure for Indonesian documentation.

Changes:

• Add EditorConfig with standardized formatting rules (UTF-8, 2-space indentation, LF line endings)
• Add Nix flake for reproducible development environment with pnpm and Node.js
• Update Astro from v5.16.8 to v5.16.10 and Starlight from v0.37.2 to v0.37.3
• Create Indonesian (id) docs directory with .gitkeep placeholder

Reviewed changes

Copilot reviewed 3 out of 6 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
.editorconfig	Defines consistent code formatting rules for all files
flake.nix	Nix flake configuration for development shell with pnpm and Node.js
flake.lock	Lock file for Nix flake dependencies
package.json	Updates Astro and Starlight dependencies to latest versions
pnpm-lock.yaml	Updated lock file reflecting new dependency versions
src/content/docs/id/.gitkeep	Placeholder for Indonesian documentation directory

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[CookieSource]

So, I see no benefit to adding NIX specific files since no one here uses NIX and unlike your PR suggests I don't see you've added a folder for the language or that you've tested updating Astro or Starlight please take a look here https://aerynos.dev/packaging/workflow/submitting-a-pr/ editorconfig maybe useful but for such a change open a discussion