## Issues from the initial attempt
- There are 2 versions of `Lbry` and `buildURI` -- the app and web-server version. There are subtle differences between them, and for the app case, importing the web-server version results in a query into an invalid URL.
- It changed the function from returning a string to returning a promise.
## Changes
- Since the new function (renamed to `fetchStreamUrl` for clarity) is currently only needed for web-server, I moved it into the `web` folder to avoid misuse in app.
- Await on the promise. Unfortunately, this also means the entire chain of function calls need to be adjusted to be `async`.
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