Initialize NX and update dependencies with changelog and tests

[flaviodelgrosso]

This pull request introduces a major restructuring of the project, migrating from Turborepo to Nx for monorepo management, and updates related tooling, configurations, and workflows to align with Nx conventions. It also removes legacy files and updates dependency management, scripts, and project structure for improved maintainability and consistency.

Monorepo Management & Build System Migration:

• Migrated the monorepo build system from Turborepo to Nx, including new Nx configuration files (project.json), updated build scripts, and changes in dependency referencing to use Nx's workspace and catalog conventions. This is a breaking change and affects all build, serve, and deploy workflows. [1] [2] [3]

• Removed Turborepo-specific files and settings, such as the apps/api/Dockerfile, .dockerignore, and related scripts, to fully transition to Nx. [1] [2]

Tooling and Workflow Updates:

• Updated CI workflow to use Nx commands for linting and typechecking, and removed steps related to environment preparation and legacy scripts.

• Replaced the pre-commit hook to use a new pnpm pre-commit script instead of lint-staged, and removed the .lintstagedrc configuration. [1] [2]

• Added and updated configuration files for Prettier, EditorConfig, and VSCode, ensuring consistent code formatting and editor behavior across the team. [1] [2] [3] [4] [5] [6]

Codebase and Dependency Refactoring:

• Updated dependency references in apps/api/package.json to use Nx workspace conventions and removed obsolete or Turborepo-specific fields. Also updated the main entry point and cleaned up scripts.

• Refactored the Fastify app bootstrap process in apps/api/src/app.ts to use a new default export and updated plugin/route registration for better compatibility with Nx.

Documentation and Environment:

• Updated the changelog to reflect the breaking change of migrating to Nx.

• Updated .env.example to include a missing BETTER_AUTH_URL variable.

Removed or Deprecated Files:

• Removed the .github/copilot-instructions.md file and old VSCode/editor settings that are no longer relevant after the migration. [1] [2]

---

Monorepo migration and build system:

• Migrated from Turborepo to Nx, including new Nx configuration files (project.json), updated dependency references, and breaking changes to build and serve workflows. [1] [2] [3]
• Removed Turborepo-specific files and scripts, such as apps/api/Dockerfile and .dockerignore. [1] [2]

Tooling and workflow updates:

• Updated CI workflow to use Nx commands and removed legacy steps; replaced pre-commit and lint-staged tooling with Nx-compatible scripts. [1] [2] [3]
• Added and updated Prettier, EditorConfig, and VSCode settings for consistent formatting and editor experience. [1] [2] [3] [4] [5]

Codebase refactoring:

• Refactored Fastify app bootstrap and plugin registration for Nx compatibility.
• Updated dependency references and cleaned up scripts in apps/api/package.json.

Documentation and environment:

• Updated changelog for Nx migration and added missing environment variable in .env.example. [1] [2]

Removed/deprecated files:

• Removed obsolete instructions, settings, and configuration files. [1] [2]