fix: AVM module upgrade changes

[Ravikirana-Microsoft]

This pull request updates the documentation and changelog for the Build Your Own Copilot solution accelerator module to reflect new Azure resource API versions, improved parameter descriptions, and compliance enhancements. The README now provides a clearer overview of the solution and lists updated supported resource types and API versions, while the changelog details improvements to parameter descriptions and validation.

Documentation improvements:

• The README.md introduction has been rewritten for clarity, now explicitly listing all major Azure resources deployed by the solution and describing its networking, monitoring, scalability, and redundancy options.

Supported resource types and API version updates:

• Updated the supported Azure resource types and their API versions in the README.md to reflect the latest stable and preview releases, including CosmosDB, Key Vault, Private Endpoints, and Storage Account resources. [1] [2] [3] [4]

Parameter documentation and compliance:

• The changelog (CHANGELOG.md) now details improvements to parameter descriptions, ensuring they comply with AVM standards (categories and punctuation), and notes enhanced parameter validation for AVM specification compliance.
• The example module usage in the README has been reorganized to show required and non-required parameters more clearly.## Description

Pipeline Reference

Pipeline

Type of Change

• Azure Verified Module updates:
  • Bugfix containing backwards-compatible bug fixes, and I have NOT bumped the MAJOR or MINOR version in version.json:
  • Feature update backwards compatible feature updates, and I have bumped the MINOR version in version.json.
  • Breaking changes and I have bumped the MAJOR version in version.json.
  • Update to documentation
• Update to CI Environment or utilities (Non-module affecting changes)

Checklist

• I'm sure there are no other open Pull Requests for the same update/change
• I have run Set-AVMModule locally to generate the supporting module files.
• My corresponding pipelines / checks run clean and green without any errors or warnings
• I have updated the module's CHANGELOG.md file with an entry for the next version