Previously, the frontend would attempt to make real requests to
`https://not-configured/`, which of course failed. I’ve changed the
internal structure to have the lack of a server expressed as a `null`
server. A new `did-bootstrap` browser-level setting has been added to
track if the user clicked “Don’t use a server.”

Finally, I updated the auth logic for methods that call out to the
server to make them consistent and use the early return style which
reduces indentation.

This is the last PR with lots of renaming for `loot-core`!

This PR converts everything (aside from electron) from CommonJS to ESM.
It is needed to reduce the changes that will happen during the migration
to Typescript (as TS does not play nice with CJS).

Basically:
- rewrite `require()` to `import`
- rewrite `module.exports` to `exports`
- introduce `ts-node` to run importers so we can convert them to TS too

Lastly, sorry for this larg-ish PR, not my preference but when I tried
to reduce its scope, I would end up with mixed commons/esm that was even
more tricky to handle.

I'm not sure if this is something you want but it was a simple change so
I figured I might as well contribute it. This PR allows the user to
upload `.blob` files that they may have gotten from server's
`user-files/` folder. This can be useful if the user didn't export the
file but has server backups.

---------

Co-authored-by: Jed Fox <git@jedfox.com>

*  (prettier) adding trailing commas

* More commas

*   upgrade eslint-plugin-import and fix issues

* Change import ordering

* style: enforce sorting of imports

* style: alphabetize imports

* style: merge duplicated imports

* style: enforce ordering of imports

* style: sort imports in loot-core

* style: sort imports in desktop-client

* style: sort imports in loot-design

* style: manual fixes