chore: add github basic apis

app/services/github/github_service.rb

@@ -0,0 +1,60 @@
+class Github::GithubService
+  attr_reader :hook
+
+  def initialize(hook:)
+    @hook = hook
+  end
+
+  def repositories
+    client.repositories(nil, type: 'all')
+  rescue Octokit::Error => e
+    Rails.logger.error("GitHub API error fetching repositories: #{e.message}")
+    raise_api_error(e)
+  end
+
+  def assignees(repo_full_name)
+    client.repository_assignees(repo_full_name)
+  rescue Octokit::Error => e
+    Rails.logger.error("GitHub API error fetching assignees for #{repo_full_name}: #{e.message}")
+    raise_api_error(e)
+  end
+
+  def search_repositories(query)
+    return repositories if query.blank?
+
+    # Get all user's repositories first
+    user_repos = repositories
+
+    # Filter repositories by query string (case-insensitive)
+    user_repos.select do |repo|
+      repo.full_name.downcase.include?(query.downcase) ||
+        (repo.description&.downcase&.include?(query.downcase))
+    end
+  rescue Octokit::Error => e
+    Rails.logger.error("GitHub API error searching repositories with query '#{query}': #{e.message}")
+    raise_api_error(e)
+  end
+
+  private
+
+  def client
+    @client ||= Octokit::Client.new(
+      access_token: hook.access_token,
+      auto_paginate: true,
+      per_page: 100
+    )
+  end
+
+  def raise_api_error(error)
+    case error.response_status
+    when 401
+      raise CustomExceptions::Base.new('GitHub authentication failed', 401)
+    when 403
+      raise CustomExceptions::Base.new('GitHub API rate limit exceeded or insufficient permissions', 403)
+    when 404
+      raise CustomExceptions::Base.new('GitHub resource not found', 404)
+    else
+      raise CustomExceptions::Base.new("GitHub API error: #{error.message}", error.response_status || 500)
+    end
+  end
+end