Completion: Dependancy graph and method db should be updated when there import changes

[laginha87]

if you have this scenario.

# File b.cr
class A
   def self.a
   end
end

# File a.cr

and then change file a.cr to:

# File a.cr
require "./b"
A.

Completion on A. doesn't work.
This is because the dependancy to b.cr wasn't added to the file.
We can either change this on save or on update. But I think on update might be really slow.

[faustinoaq]

@laginha87 Is this already fixed?😅

[faustinoaq]

I think we can execute something similar to @workspace.open_workspace here: https://github.com/crystal-lang-tools/scry/blob/master/src/scry/context.cr#L165

Perhaps just ignoring existent files and adding new ones, WDYT?