Fix | Login flow fails if performed immediately after logging out

[n370]

Closes: #17

This PR adds:

• Wraps third-party async functions in try/catch blocks where appropriate setting the pattern for proper error handling in the future.
• Preload static assets using the expo-asset library.
• Bumps expo-auth-session library to new version that fixes the login issue.

[n370]

@simoneb you may want to keep this branch around and use it to add the commit upgrading the auth library when the fixed version is ready. If you do so you can take advantage of a few small improvements I made here while looking for what was causing this issue.

[n370]

@simoneb I'm not sure you want this draft to stay around any longer. Did y'all found a solution for this already?

[simoneb]

@simoneb I'm not sure you want this draft to stay around any longer. Did y'all found a solution for this already?

Let's keep it here for reference until it's solved. We know what the issue is but your work here may be useful nonetheless. I'll keep track of this, no worries.