[.NET Migration Guide Revamp] [Phase 1] Move content 'Deal primarily with the compiler' content from 'Port libraries' page.

[StephenBonikowsky]

For details on revamp see: #23561
New TOC: #23215

• Deal primarily with the compiler (MOVE) This section needs to be moved to a new location in the new TOC and updated as needed.

• Stay on the .NET Framework until portability issues are resolved (MOVE) This section needs to be moved to a new location in the new TOC and updated as needed.

• Develop a comprehensive plan of attack (MOVE) This section needs to be moved to a new location in the new TOC and updated as needed.

• Mixed approach (MOVE) This section needs to be moved to a new location in the new TOC and updated as needed.

• Port your tests (MOVE) This section needs to be moved to a new location in the new TOC and updated as needed.

• Recommended approach (MOVE) This section needs to be moved to a new location in the new TOC and updated as needed.

• name: Migration guide
  items:

  • name: Overview
    href: ../core/porting/index.md
  • name: General Information
    items:
  • name: Pre-Migration
    items:
  • name: Migration
    items:
    • name: Create a porting plan
      href: ../core/porting/create-a-porting-plan.md

[StephenBonikowsky]

Completed with #24630