CSTM-190: Adding UI Plugins Command Group and stubbing out subcommands

[jeremy-gooch-sp]

Description

This PR adds the foundational work for UI Plugins by setting up a new command group and stubbing out the various sub commands that will be completed in follow on tickets as part of the epic for CSTM-232.

How Has This Been Tested?

Set the environment variable SAIL_EXPERIMENTAL_UI_PLUGINS to 1 and ran the project's ui-plugin command and verified the output

   UI Plugins                                                                 
                                                                              
  Manage UI Plugin workflows in Identity Security Cloud.                      
                                                                              
  This command group is currently experimental and hidden from default command
  discovery. Enable it for development with:                                  
                                                                              
    export SAIL_EXPERIMENTAL_UI_PLUGINS=1                                     
                                                                              
  Planned workflow commands:                                                  
                                                                              
  • init                                                                      
  • create                                                                    
  • link                                                                      
  • update                                                                    
  • upload                                                                    
  • list                                                                      
  • delete                                                                    

Usage:
  sail ui-plugins [flags]
  sail ui-plugins [command]

Examples:

                                                                              
    sail ui-plugins                                                           
    SAIL_EXPERIMENTAL_UI_PLUGINS=1 sail ui-plugins init                       



Available Commands:
  create      Create a UI plugin instance in the current tenant
  delete      Delete a UI plugin instance
  init        Initialize a UI plugin workspace
  link        Link local development URL for a UI plugin
  list        List UI plugin instances in the current tenant
  update      Update a UI plugin manifest configuration
  upload      Upload compiled UI plugin assets

Flags:
  -h, --help   help for ui-plugins

Global Flags:
      --debug        Enable debug logging
      --env string   Environment to use for SailPoint CLI commands

Use "sail ui-plugins [command] --help" for more information about a command.

Running specific stub commands results in: Error: 'sail ui-plugins <command>' is not implemented yet

[CLAassistant]

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