[ENH] - Option to set a custom name for an app

[pmeier]

Feature description

Add an option to set a custom name for a deployed app instead of assigning it a random ID. If the name is already used by a different app, the form should display an error.

Value and/or benefit

1. Apps that are deployed (semi-)permanently could have a human digestible and memorable URL.
2. Apps that need to know the path prefix before they are deployed, e.g. FastAPI, can be deployed in a single step. Right now, the only way to do this is to deploy once, which will fail as expected. At that point the prefix is known and we can restart the app and supplying the prefix.

Anything else?

Talked with @aktech about this offline.

[aktech]

So, one way to tackle this in short term is to get rid of the random suffix and only add it when the name is taken, so:

1. first app

if the user name's their app as: Awesome Panel App
the url will be: awesome-panel-app

2. second app

If the user name's ANOTHER of their apps as: Awesome Panel App,
now the url will be something like: awesome-panel-app-d2598a as awesome-panel-app is taken by the first app

This approach makes the resulting url deterministic, without complicating the UI.

[pmeier]

This approach makes the resulting url deterministic, without complicating the UI.

This approach makes the first resulting url deterministic, without complicating the UI.

This is good enough for the use case I have in mind, but shouldn't be more than a stop gap until proper UI error is being implemented.