Get rid of SELECT * FROM *

[Centril]

This issue is meant to track the eventual removal of SELECT * FROM * because as @gefjon says, it is deeply cursed and evil.

[gefjon]

More specifically:

• It is a weird non-SQL fragment.
• We have to decide where it is and isn't valid: can I spacetime sql my-module 'SELECT * FROM *' from the command-line? Can I issue it as a one-off query? Can it coexist with other queries in a subscription?
• We want to encourage client authors to subscribe only to the data they need, but SELECT * FROM * encourages the opposite.