Bicep good first issues

This issue requests an enhancement to the `loadYamlContent()` function in Bicep. Currently, it provides a generic error message when encountering multi-document YAML files, which are technically valid. The desired solution is a more specific error message indicating that multi-document YAML is not supported.

This issue proposes a new linter rule for Bicep to detect and warn against the use of the `resourceId()` function to reference child resources, specifically subnets within virtual networks. The goal is to encourage a more idiomatic and maintainable approach using `existing` resources and direct property access for better readability and type safety.

This issue proposes enhancing the functionality of `@onlyIfNotExists` to allow for the creation of Key Vault entries that automatically expire. This would involve adding support for expiration dates when creating new secrets or keys, improving automated secret management.

This issue requests disabling outbound UDP connections on port 65330 within a custom image template. This is necessary because port 65330 is reserved by Azure VNets, and blocking it can prevent DNS timeout issues as described in the provided Microsoft blog post.

This enhancement request aims to configure all subnets within the project to be private. The issue is labeled as a 'good first issue', suggesting it's suitable for newcomers and likely involves straightforward configuration changes rather than complex architectural modifications.

The task is to contribute to a discussion on Bicep best practices by sharing personal experiences, identifying anti-patterns, suggesting improvements, and linking to helpful resources. This will help shape future Bicep tooling, documentation, and community standards.

The task is to modify the GitHub Copilot Metrics Viewer application to handle cases where the GitHub Copilot Metrics API returns data beyond the expected 28-day window. The application currently displays data for the 'Last 28 days' but is showing more, leading to misleading information. The solution should make the application robust to changes in the API's date range, ensuring it only processes and displays the most recent 28 days of data regardless of what the API returns.