fix: Remove LoadingNetworkScreen overlay

[legobeat]

Description

In scenarios where connectivity to the currently configured network is not available, most actions are not available and hidden behind a "Connecting to Infura Mainnet..." overlay. This includes the "Add custom network" functionality, which creates a catch-22 for users relying on custom RPC endpoints: They can not configure their network because the configured network is not available...

In fact, why block any sections of the UI because the configured RPC endpoint is not currently reachable?

This removes the blocking loading-overlay triggering completely.

Related issues

• [Bug]: Can not add custom network during onboarding #23333

Manual testing steps

1. State: Onboarded wallet with default settings (Infura mainnet)
2. Remove Infura connectivity while maintaining connectivity to a separate Eth Mainnet RPC endpoint
3. Unlock wallet and configure custom RPC endpoint

Screenshots/Recordings

Before

After

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[github-actions]

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[danjm]

We need to inform the user if there is a failure to connect to the currently configured network. The loading screen does that today. How will we do that if the loading screen is removed?

[github-actions]

This PR has been automatically marked as stale because it has not had recent activity in the last 60 days. It will be closed in 14 days. Thank you for your contributions.

[github-actions]

This PR was closed because there has been no follow up activity in the last 14 days. Thank you for your contributions.