fix: azd template validation pipeline issue

[Priyanka-Microsoft]

Purpose

• ...
  This pull request introduces improvements to documentation structure and updates infrastructure deployment configuration. The most significant changes include reorganizing the README.md for better clarity and updating the Bicep module path in the infrastructure code.

Documentation improvements:

• Added new sections to README.md for Features, Getting Started, Guidance, and Resources to improve organization and make it easier for users to find key information. [1] [2] [3] [4]

Infrastructure configuration:

• Updated the Bicep module path in infra/main.bicep to reference the correct infra/main.bicep file within the ai-landing-zone submodule, ensuring the deployment uses the intended infrastructure template.

CI/CD workflow:

• Modified .github/workflows/azd-template-validation.yml to trigger on pull requests to the main branch, in addition to pushes, improving workflow coverage.

Does this introduce a breaking change?

• Yes
• No

Golden Path Validation

• I have tested the primary workflows (the "golden path") to ensure they function correctly without errors.

Deployment Validation

• I have validated the deployment process successfully and all services are running as expected with this change.

What to Check

Verify that the following are valid

• ...

Other Information