Fix: insufficient proposal balance issue

[kneerose]

List of changes

• Add an extra temporary wallet for proposal submission to support balance-dependent test cases 7J_1, 7J_2, 7K, and 8U.
• Implement a test prompt to display an insufficient balance modal when the wallet balance is inadequate after clicking the "Submit as a Governance Action" button.
• Configure the authentication setup for the proposal submission balance-dependent wallet.
• Update the project structure and README to reflect the revised flow for proposal discussion.
• Fix the reply testId issue in the budget proposal.
• Log wallet details during proposal submission for governance action tests.

Checklist

• related issue
• My changes generate no new warnings
• My code follows the style guidelines of this project
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the changelog
• I have added tests that prove my fix is effective or that my feature works

[github-actions]

✅ All checks succeeded

[github-actions]

✅ All checks succeeded

[github-actions]

✅ All checks succeeded

[github-actions]

@kneerose
This PR is in the tag: develop-6c145b74acba99e62b702adfb7798f52f090154f , for govtool-backend service

[github-actions]

@kneerose
This PR is in the tag: develop-6c145b74acba99e62b702adfb7798f52f090154f , for govtool-metadata-validation service

[github-actions]

@kneerose
This PR is in the tag: develop-6c145b74acba99e62b702adfb7798f52f090154f , for govtool-frontend service