Updated Policies documentation to prepare for general availability release and improved usability with UI editor workflow.

Getting started changes

• Removed alpha/preview warnings and callouts
• Updated "Enforceable Policies" section to "What can you enforce with policies?" with expanded use cases
• Completely rewrote getting started guide to focus on UI editor workflow instead of OCL files
• Added new sections for committing, publishing, and activating policies through the UI
• Updated to reflect modern Platform Hub repository setup

Example updates

• Changed from OCL-file-only format to UI editor-first approach
• Added "How to use these examples" section explaining both UI editor and OCL file workflows
• Removed metadata (name, description, violation_reason) from all examples
• Simplified all examples to show only Rego code blocks suitable for copy-paste into UI editor
• Split examples into "Scoping examples" and "Conditions examples" sections
• Changed code block syntax highlighting from rego to ruby

Added new examples:

• Scope example for excluding specific projects
• Conditions example for checking no parallel execution
• Moved OCL file format documentation to end of page as alternative approach
• Updated package names to match policy slugs consistently

Best practices update:

• Added new section "Check for parallel execution"
• Explains StartTrigger property values (StartAfterPrevious vs StartWithPrevious)
• References examples page for implementation

Added troubleshooting

Documents Windows Server missing Visual C++ Redistributable dependency issue

These changes prepare the Policies documentation for general availability by removing alpha warnings, restructuring examples for better usability with the new UI editor, and adding practical guidance for common use cases.