fix(mongo): dropping a database, collection, or document must confirm #781

Summary

SQL workspaces use showDestructiveQueryDialog. Mongo Drop database / Drop collection / document Del call dropDatabase / dropCollection / deleteOne with no confirm.

Scope

• Same destructive dialog (or Mongo-specific copy) before drop/delete.
• Cancel must not call the service.
• Widget/integration coverage for cancel path.

Out of scope

• Recycle bin / undo.