Presenting Database Errors

Launchpad should handle database errors more gracefully. In many cases, database errors are caused by the correct enforcement of database contraints. Currently, that causes a server error (500) rather than giving the user reasonable feedback about what they tried to do.

For example, if you try to add a specification to a product with the same name as an existing specification, you will see a "server error". What is really happening is that the database constraint on name uniqueness is being violated, trigerring a database error and then a launchpad server error. Instead, the user should see a meaningful alert and have the opportunity to correct it.