Add lefthook for precommit hook

[jderochervlk]

Running format will save a lot of headaches before pushing.

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[Copilot]

Pull request overview

This PR adds lefthook as a pre-commit hook to automatically run code formatting before commits, helping maintain consistent code style across the project.

Key Changes:

• Added lefthook v2.0.4 as a dev dependency
• Created lefthook.yml configuration to run yarn format on pre-commit
• The hook will automatically stage formatted files

Reviewed changes

Copilot reviewed 2 out of 3 changed files in this pull request and generated 3 comments.

File	Description
package.json	Adds lefthook ^2.0.4 as a dev dependency
yarn.lock	Updates lock file with lefthook package and platform-specific binaries
lefthook.yml	Creates new lefthook configuration for pre-commit hook with format command

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[Copilot]

Missing postinstall script to install lefthook git hooks. After adding lefthook as a dependency, developers need to run lefthook install to actually install the git hooks. Without this, the pre-commit hook won't be activated.

Consider adding a postinstall script to package.json:

"scripts": {
  "postinstall": "lefthook install"
}

This ensures the git hooks are automatically installed when developers run yarn install.

[Copilot]

Incorrect syntax for lefthook configuration. The jobs array syntax is not valid for lefthook v2. Job commands should be defined as named keys, not as array items.

The correct syntax should be:

pre-commit:
  parallel: true
  commands:
    format:
      run: yarn format
      stage_fixed: true

Alternatively, you can use the shorter syntax:

pre-commit:
  commands:
    format:
      run: yarn format
      stage_fixed: true

Suggested change

	jobs:
	- run: yarn format
	commands:
	format:
	run: yarn format

[Copilot]

Consider adding a comment at the top of the lefthook configuration file to explain its purpose and how to set it up. For example:

# Lefthook configuration for git hooks
# Runs formatting before commits to ensure code quality
# Install hooks by running: yarn install (or npx lefthook install)

This helps other developers understand the purpose of this file and how to use it.