unexpected behaviour when defining multiple entries inside routesDir

[vkunz]

hi,

bug description

Running routify build with the following options does
not override the defaults, but merges the user provided
options with the defaults. This is unexpected.

        const options = {
            routesDir: {
                "foo": "src/routes/foo",
                "bar": "src/routes/bar"
            }
        }

        const routify = new RoutifyBuildtime(options);

        routify.start();

I would have expected routify to create two routes bundles, one
called foo, one called bar.

Instead both default configs and user provided configs are merged,
and routify tries to create three routes bundles, foo, bar and default.

Because I renamed default to foo, src/routes is now empty, thus routify can't find any routes and errors out.

error:

[Routify 3] build triggered by initial
Error: ENOENT: no such file or directory, stat 'src/routes'

I have a test here that demonstrates unexpected behaviour.

I am not sure if deepAssign is actually wrong, or the usage of deepAssign.
It is just the source of the behaviour.

system:

OS: Linux 5.10 Debian GNU/Linux 11 (bullseye) 11 (bullseye)
CPU: (8) x64 Intel(R) Xeon(R) CPU E3-1270 v5 @ 3.60GHz
  

node:

Node: 16.17.0 - /tmp/xfs-6ba2d18b/node
Yarn: 3.2.3 - /tmp/xfs-6ba2d18b/yarn
npm: 8.15.0 - /usr/bin/npm
  

package.json

  - "svelte": "3.50.0"
  - "@roxi/routify": "3.0.0-next.115"