Added Ruby gem compatibility (#3)

### Description 

This PR resolved #1 and added the `secure-keys.gemspec` file adding the
ruby gem compatibilty.

Currently, the gem is published officially on [Ruby gem
page](https://rubygems.org/gems/secure-keys).

To install the gem, run the following commands:

```bash
gem install secure-keys
```

or using bundler:

```ruby
# Gemfile

gem 'secure-keys'
```

Install dependencies:

```bash
bundle install
```

### Medias (if needed)

<img width="958" alt="image"
src="https://github.com/user-attachments/assets/b3a8f771-6aad-49d1-85b8-a0dc6a7885e3"
/>

### Testplan

- [x] I tested this change on my local environment.
- [ ] I ran the unit tests.

### Checklist

- [ ] I added tests for this change.
- [x] I checked the code style and run the linter.
- [x] I added necessary documentation (if applicable).

.gitignore

@@ -2,3 +2,6 @@
 
 # XCFramework files
 .keys/
+
+# Gem files
+secure-keys-*.gem

Gemfile

@@ -4,8 +4,4 @@ source 'https://rubygems.org'
 
 ruby file: '.ruby-version'
 
-gem 'base64'
-gem 'digest'
-gem 'json'
-gem 'osx_keychain'
-gem 'rubocop', require: false
+gemspec path: '.'

Gemfile.lock

@@ -1,3 +1,12 @@
+PATH
+  remote: .
+  specs:
+    secure-keys (1.0.3)
+      base64 (~> 0.2.0)
+      digest (~> 3.2.0)
+      json (~> 2.10.1)
+      osx_keychain (~> 1.0.2)
+
 GEM
   remote: https://rubygems.org/
   specs:
@@ -40,11 +49,8 @@ PLATFORMS
   ruby
 
 DEPENDENCIES
-  base64
-  digest
-  json
-  osx_keychain
-  rubocop
+  rubocop (~> 1.71.2)
+  secure-keys!
 
 RUBY VERSION
    ruby 3.3.6p108

README.md

@@ -18,16 +18,22 @@ Utility to generate a `xcframework` for handling secure keys in iOS projects.
 
 ### Installation
 
-Install gems using bundler
+You can install the `Keys` utility using `gem` command:
 
 ```bash
-bundle install
+gem install secure-keys
 ```
 
-If you don't have bundler installed, you can install it using:
+If you using `bundler` you can add the `secure-keys` gem to the `Gemfile`:
+
+```ruby
+gem 'secure-keys'
+```
+
+Then, you can install the gem using:
 
 ```bash
-gem install bundler
+bundle install
 ```
 
 ## Usage
@@ -95,10 +101,18 @@ export SECURE_KEYS_IDENTIFIER="github-token|api_key|firebaseToken"
 
 ### Ruby script
 
-To generate the `Keys.xcframework` use the `keys.rb` script with:
+To generate the `Keys.xcframework` use the `secure-keys` command in the iOS project root directory.
+
+Using global gem:
+
+```bash
+secure-keys
+```
+
+Using bundler:
 
 ```bash
-bundle exec ruby ./bin/keys.rb
+bundle exec secure-keys
 ```
 
 ### iOS project

lib/version.rb

@@ -1,6 +1,7 @@
 #!/usr/bin/env ruby
 
 module Keys
-  VERSION = '1.0.0'.freeze
+  VERSION = '1.0.3'.freeze
+  SUMMARY = 'Keys is a simple tool for managing your secret keys'.freeze
   DESCRIPTION = 'Keys is a simple tool to manage your secret keys in iOS your project'.freeze
 end

secure-keys.gemspec

@@ -0,0 +1,37 @@
+#!/usr/bin/env ruby
+
+lib = File.expand_path('lib', __dir__)
+$LOAD_PATH.unshift(lib) unless $LOAD_PATH.include?(lib)
+
+require "#{Dir.pwd}/lib/version"
+
+Gem::Specification.new do |spec|
+  spec.required_ruby_version = '>= 3.3'
+  spec.required_rubygems_version = Gem::Requirement.new('>= 0'.freeze) if spec.respond_to? :required_rubygems_version=
+
+  spec.name           = 'secure-keys'
+  spec.version        = Keys::VERSION
+  spec.authors        = ['Derian Córdoba']
+  spec.email          = ['derianricardo451@gmail.com']
+  spec.summary        = Keys::SUMMARY
+  spec.description    = Keys::DESCRIPTION
+  spec.license        = 'MIT'
+  spec.homepage       = 'https://github.com/DerianCordobaPerez/secure-keys-generator'
+  spec.bindir         = 'bin'
+  spec.require_paths  = %w[*/lib]
+  spec.platform       = Gem::Platform::RUBY
+
+  spec.metadata['homepage_uri'] = spec.homepage
+  spec.metadata['source_code_uri'] = spec.homepage
+  spec.metadata['changelog_uri'] = "#{spec.homepage}/releases"
+
+  spec.files = Dir.glob('*/lib/**/*',
+                        File::FNM_DOTMATCH) + Dir['bin/*'] + Dir['*/README.md'] + %w[README.md]
+  spec.executables = spec.files.grep(%r{^bin/}) { |file| File.basename(file) }
+
+  spec.add_runtime_dependency 'base64', '~> 0.2.0'
+  spec.add_runtime_dependency 'digest', '~> 3.2.0'
+  spec.add_runtime_dependency 'json', '~> 2.10.1'
+  spec.add_runtime_dependency 'osx_keychain', '~> 1.0.2'
+  spec.add_development_dependency 'rubocop', '~> 1.71.2'
+end