Be more pro-active in suggesting to initialize an uninitialized project

[vpetrovykh]

Currently if you run edgedb inside an uninitialized project that already has an edgedb.toml you get an error:

$ edgedb
edgedb error: project is not initialized and no connection options are specified
  Hint: Run `edgedb project init` or use any of `-H`, `-P`, `-I` arguments to specify connection parameters. See `--help` for details

However, the CLI could instead ask the user if they want to initialize the project now. Something like:

Found `edgedb.toml` but the project is not initialized. Would you like to initialize it now? (y/N)

This prompt to initialize the project probably should default to "No" because it's not necessarily something you want to accidentally do (it's not a lightweight operation).