feat: harden npm publish & make installer leaner

[o-az]

Motivation

Solution

PR Checklist

• Added Tests
• Added Documentation
• Breaking changes

[grandizzy]

lgtm, thank you!

[Copilot]

Pull Request Overview

This PR hardens the npm publish process and makes the installer leaner by adding security checks, improving error handling, and removing unused files.

• Added security hardening with HTTPS enforcement and integrity verification for package downloads
• Removed test workspace files and unused index.ts module to reduce package size
• Improved error messages and consolidated platform detection logic

Reviewed Changes

Copilot reviewed 23 out of 25 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
npm/tsdown.config.ts	Removed unused index build configuration
npm/test/workspace/*	Removed test workspace files and configuration
npm/src/install.ts	Added security checks, improved integrity verification, and enhanced error handling
npm/src/index.ts	Deleted unused module
npm/src/forge.ts	Simplified binary path resolution using shared constants
npm/scripts/publish.ts	Updated import path and nightly detection logic
npm/scripts/prepublish.ts	Removed Alpine Linux support and improved directory handling
npm/package.json	Added import mappings and updated dependencies
npm/README.md	Simplified documentation
npm/@foundry-rs/forge/package.json	Removed main entry and engines field
npm/@foundry-rs/forge/README.md	Updated package description
npm/@foundry-rs/forge-*/package.json	Reset versions to 0.0.0
npm/.env.example	Added security-related environment variables
dprint.json	Updated plugin versions
.github/workflows/npm.yml	Improved artifact handling and action security
.gitattributes	Added linguist language detection for .env.example

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[zerosnacks]

Thanks! Looks good