[FR] Drag and drop support

[ikeofkc]

Please add drag and drop support to the launch similar to cosmic-applibrary

Possible use cases

• Drag application to dock or panel (main)
• Drag application to workspace widget to launch on specific workspace. (And hopefully in the future via the workspaces view with type to search launcher implemented in workspaces view issue )
• Add creative new use cases like drag a text result to a text field (random idea)