feat!: release MCPM v2.0 with major architectural changes

  BREAKING CHANGE: MCPM v2.0 introduces a completely new architecture that
  eliminates the target-based system in favor of a simplified global
  configuration model with virtual profiles.

  Major changes:
  - Removed target-based commands (mcpm target, mcpm stash, mcpm pop, etc.)
  - Replaced with global server management (mcpm install/uninstall)
  - Virtual profiles replace separate profile configurations
  - Direct server execution replaces router daemon
  - New client integration commands (mcpm client edit/import)
  - FastMCP-based sharing instead of router sharing
  - Automatic v1 to v2 migration with user confirmation

  This release requires migration from v1 configurations and changes
  command syntax. See MIGRATION_GUIDE.md for complete migration instructions.

Author: niechen