feat: Add Write-ADOMessage function for colored logging in Azure DevOps

[sikksakk]

This pull request adds a new Write-ADOMessage function to the Azure DevOps Logging module, enabling colored messages in pipeline logs using ANSI color codes. It also updates the module manifest to export this new function and introduces internal mappings for color codes.

New Feature: Colored Message Output

• Added the Write-ADOMessage function to allow writing messages with customizable foreground and background colors in Azure DevOps pipeline logs, supporting ANSI 4-bit color codes and an option to suppress newlines. (AzureDevOpsLogging/Public/Write-ADOMessage.ps1)
• Introduced $script:ForegroundColorMap and $script:BackgroundColorMap in the module to map color names to their corresponding ANSI codes, supporting the new message function. (AzureDevOpsLogging/AzureDevOpsLogging.psm1)

Module Manifest Update

• Updated the FunctionsToExport list in the module manifest to include Write-ADOMessage, making the new function available for use when the module is imported. (AzureDevOpsLogging/AzureDevOpsLogging.psd1)