Allow stable Session Naming for ephemeral sessions

### Is your feature request related to a problem? Please describe.

Right now, the Session/Workspace name is set-able when creating non-ephemeral sessions.
The following code shows how to create a session with predictable name:
```JS
const launchRequest = {
serviceUrl: config.serviceUrl,
appId: config.appId,
user: email!,
appDefinition: appDefinition,
workspaceName: 'we-can-set-every-value-here',
```
but this parameter is ignored for ephemeral sessions. The session's name would be `we-can-set-every-value-here-session`.

This allows to create two sessions with the same name, both resolving to the same workspace, and, thus, restarting and reconnecting the user to the workspace. This is **good** and actually very useful functionality.

Still, it seems like unintended functionality to allow such behavior on non-ephermal sessions but not on ephemeral ones. Maybe, this mechanisms allows to bring the system in a unpredicted state by choosing weird names?

### Describe the solution you'd like

We want a controllable way to set the session name (regardless of persistency). The session names are currently calculated in regard to the `user` and the `appDefinition`, giving us no flexibility to add dynamic data fetched via the landing page to it (exerciseId).

In our use case it is required to (re)identify a running session and have the user connect to it. This could be solved with either setting the name ourselves or being able to predict the names in a stable and extensible way.

### Describe alternatives you've considered

It would also be able to define some flags/options during session/workspace creation to later identify it with.

### Cluster provider

_No response_

### Additional information

_No response_

No file or test is named. Start by tracing session/workspace creation and the logic that calculates names from the user and appDefinition, comparing ephemeral and non-ephemeral paths. Done means a stable, controllable naming or identification mechanism works for both persistence modes and prevents unintended collisions.

Written by the indexing model from the issue text.