Lang: Module import syntax

[phated]

This was discussed in another issue, but I can't find it quickly so I wanted to open a top-level issue. If you find the discussion, please link.

To improve LSP support (and general code readability), we plan to change the module importing syntax from "file last" to "file first". While not the final syntax, this could look something like:

from "foo" import { bar }

This will likely be a part of the larger module system rewrite that includes module definitions inside files, new foreign syntax, and type exports.