Add support to Enterprise level metrics

[martedesco]

This pull request introduces changes to enhance the functionality of the application and improve the user experience. The most significant changes include the addition of environment variables to control the scope of API calls and changes to the API to support different scopes. These changes allow the application to target API calls to either an enterprise or an organization.

Environment Variables and API Calls:

• .env: Introduced new environment variables VUE_APP_SCOPE and VUE_APP_GITHUB_ENT to determine the scope of the API calls and the enterprise or organization name to target API calls, respectively.
• src/api/GitHubApi.ts: Renamed getGitHubCopilotMetricsApi to getMetricsApi and modified it to use the new environment variables to determine the API endpoint. Also, added a new method getTeams to fetch teams data. [1] [2]

User Interface and User Experience:

• src/components/ApiResponse.vue: Added a copy to clipboard feature for the JSON response displayed in the UI. [1] [2] [3]
• src/components/MainComponent.vue: Updated the toolbar title to include the capitalized item name and the GitHub organization name. Also, added error handling for an invalid scope in the .env file. [1] [2] [3] [4]

Documentation and Version Updates:

• README.md: Updated the setup instructions to include the new environment variables and their usage. Also, updated the "Coming next" section. [1] [2]
• package.json: Updated the project version from 1.2.0 to 1.4.0 - preparing for release.

Minor Changes:

• public/index.html: Updated the favicon from .ico to .svg.
• Removed src/components/RawDataViewer.vue file.