Include candid file in Canister Metadata

[MykleNero]

The User canister (and possibly others) doesn't have the candid file included in the Canister Metadata. I'm not sure if this is intentional or not but thought it was worth calling out. This issue presents itself when using the Candid UI. Users can manually provide the candid file along with their canister id but this requires a bit of work to do.

The steps I took to be able to view the API:

1. Clone the repo
2. Find and edit the candid file for the User canister so that there are no import statements
3. Provide Candid UI with canister principal and candid file

Not terrible, but having the .did file included in Canister Metadata would simplify this a ton for anyone coming along in the future!