SignalR tutorial: Client Side Library Install

### Description

Hi, I'm thinking it might be good to mention an alternate way of adding a client-side library via the file system. This can be helpful for users who may want to use npm instead of unpkg to install SignalR. However, it doesn't work if I only add files from the dist/browser folder so I have to include all library files, and in fact that doesn't always seem to work either. Alternatively the user could just manually copy the entire signalr folder into the js folder, and then Visual Studio seems to add the folder to the project automatically at some point after building or running it; I'm thinking this could also be a bug in Visual Studio.

Also, if I only add the mentioned files from unpkg I get warnings in the console about other debugging files like map files not being present.

### Page URL

https://learn.microsoft.com/en-us/aspnet/core/tutorials/signalr?view=aspnetcore-9.0&tabs=visual-studio

### Content source URL

https://github.com/dotnet/AspNetCore.Docs/blob/main/aspnetcore/tutorials/signalr.md

### Document ID

5e3fbe1d-c97f-9940-4f0c-067d4b2112b1

### Article author

@bradygaster

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