Added Basic Authentication feature

[pratapsingh9]

PR Description

This PR adds support for Basic Authentication by introducing username and password fields for both GraphQL and REST APIs in the API Dash repo. I’ve also added a new authorization tab to make it easier to configure auth credentials.

Summary of Changes

• Added a new TabBar widget for managing API authorization.
• Created a provider for auth credentials to handle state efficiently.
• Implemented methods to:
  • Update authentication type (None, Basic Auth, etc.).
  • Update username and password credentials dynamically.
  • Generate authentication headers and apply them to API requests.
• Made sure everything works smoothly for both GraphQL and REST APIs.

Related Issues

• Closes Add API Auth: Basic authentication #610

Screenshots

Checklist

• I have gone through the contributing guide
• I have updated my branch and synced it with project main branch before making this PR
• I am using the latest Flutter stable branch (run flutter upgrade and verify)
• I have run the tests (flutter test) and all tests are passing

Added/updated tests?

We encourage you to add relevant test cases.

• Yes
• No, and this is why: please replace this line with details on why tests have not been included

OS on which you have developed and tested the feature?

• Windows
• macOS
• Linux

[ashitaprasad]

There is no separation of UI & logic.
If headers, params, body, everyone uses the same provider why have you created a separate provider for handling Auth.