....

What are the code requirements for this application (simple 110 V, 14
gage
wire) ?
I doubt that the regular NM-14 has an appropriate sheathing for this
application ?

What type of wire is code approved for this type of application, and
what would I want ?

Any caveats or not apparent or obvious Code requirements ?

....

The only way to answer those questions is to talk to your local Code
Enforcement Office to see what the specific rules for your own locale
are. Every location tends to have slightly different requirements.