Refactor the UI to be more user-friendly

[JulienVig]

This issue addresses the overall web app structure, taking a step back from implementation details to look at the website's objectives and user experience. The following contains reflections and to-dos stemming from my personal experience navigating the DISCO website without any prior knowledge. Some items are questions rather than to-dos to emphasize what may be unclear or confusing to new users.

TLDR:

1. Restructure the website navigation
2. Make showcase training (preexisting tasks) much faster (minimize the number of clicks a new user has to make between landing on the homepage and having evaluating a model)
3. Make the custom training (creating and joining custom tasks) the center of the website since this is what most users will use DISCO for.

Current problems

• The navigation is confusing and sometimes unintuitive
• What are preexisting tasks is unclear at first. They are examples, and that should be immediately obvious.
• Preexisting tasks take too much "effort" to train a model (i.e. clicks, navigate pages, upload datasets)
• The website is oriented towards preexisting tasks while it should be oriented towards custom training.
• What's the difference between a DISCOllaborative, a task and a custom task?
• How do you connect to an existing DISCOllaborative?

Changes

Refactor the navigation

This is the main item of this issue. The website navigation isn't clear for newcomers, it is hard to realize there are different ways with different names to get to the same page (for example, clicking on Train from the homepage gets you to the Preexisting task list, which you can also reach from the sidebar menu). Restructure the website to make navigation coherent, intuitive and centered around custom training:

• Homepage button should be more intuitive, e.g. "Join a DISCOllaborative to train a model" is misleading. It actually points to preexisting tasks as examples while a user may understand it as "train your own model"
• "Evaluate your DISCO-trained model" should also specify that users can download pre-trained model
• Sidebar menu "Task" tab should be renamed Examples
• Custom training should be in the sidebar menu too

Rework preexisting tasks

The purpose of preexisting tasks is unclear. Despite what the home page says, it is not for training your model but to showcase how DISCO works. When I first got on the website, the intuitive navigation flow of the website led me to preexisting tasks. Given that I want to train my own model with my own data, I was confused at why I couldn't upload a model and couldn't change the hyperparameters. Why do I have to upload data if it's a preexisting task?

• Rename preexisting tasks as Examples
• Make preexisting tasks much easier: minimize the number of clicks a new user has to make between landing on the homepage and having evaluating a model.
• We should already have datasets ready rather than ask users to download it manually. And if we need to ask users to download it manually, we should do so in the “Connect Your Data” step rather than the “Task Description” and ask more clearly. Create a "Use default dataset" button and let people choose if they want to go to the extra step of uploading their own data.
• There seems to be a lot of overlap between the preexisting tasks, made select a few distinctive ones and improve the quality rather than the quantity.
• Why is the dataset text button called "Join"?

Homepage and Information

• The Information page content should be in the homepage because it is so essential. For example, the homepage could be scrollable, with each information step per screen and the getting started buttons at the bottom. Experienced users can navigate quickly from the sidebar menu.
• What are, and what's the difference between distributed and collaborative? Maybe add simple sentences in the body making clear what distributed and collaborative are.
• It is not clear that a use case is to connect to existing DISCOllaborative session

Model Library and Settings

• Put the only setting in the model library rather than a whole menu tab, especially since it influences the Model Library behavior. If the setting is turned off the model library doesn't work, so it should be accessible from the library. Future setting can go in the Setting Page but until then the page is superfluous.