Add GitHub Packages Support to MCP Server

### Describe the feature or problem you’d like to solve

GitHub Packages is a widely-used package hosting service integrated with GitHub repositories, supporting multiple package ecosystems (npm, Maven, Docker, RubyGems, NuGet, etc.). Currently, the GitHub MCP Server lacks tools to interact with GitHub Packages, preventing AI agents from helping users with package management workflows

### Proposed solution

Add a new packages toolset

Supported Package Types
npm, maven, rubygems, docker, nuget, container

### Example prompts or workflows (for tools/toolsets only)

- "Show me all Docker packages in the 'acme-corp' organization that are marked as public"

Uses list_org_packages with package_type: docker and [visibility: public](vscode-file://vscode-app/private/var/folders/jv/n9kbzdg502s1s8dk5bb0chqr0000gn/T/AppTranslocation/859B28F9-8458-4BA1-86B0-4CCAE4A6D3E9/d/Visual%20Studio%20Code.app/Contents/Resources/app/out/vs/code/electron-sandbox/workbench/workbench.html)

- "List all versions of the 'api-client' npm package in our organization,
and delete any versions older than v1.0.0"

Uses list_package_versions followed by selective delete_org_package_version calls

- "Show me details about the 'frontend-components' package version 2.3.1
in our organization"

Uses get_package_version to retrieve metadata

- "We're migrating from 'old-org' to 'new-org'.
List all Maven packages in old-org so we can plan the migration"

Uses list_org_packages with package_type: maven and pagination