feat: connection issues view

[jvsena42]

Related to #873

Description

This PR adds a reusable connection issues overlay view and improves network recovery behavior across multiple flows.

Connection Issues Overlay

• Adds ConnectionIssuesView composable with phone illustration, dashed gradient rings, and a loading spinner
• Integrates the overlay into SendSheet, ReceiveSheet, ForceTransferSheet, SpendingAmountScreen, SpendingConfirmScreen, and SavingsConfirmScreen using AnimatedVisibility
• Auto-dismisses when connectivity is restored, preserving the underlying flow state

Network Recovery Improvements

• LightningRepo.canSend() fallback: When channels are loading (node Starting or channels not yet usable after reconnect), falls back to cached totalLightningSats balance instead of returning false — fixes unified invoices only showing savings option after reconnecting
• SpendingAmountScreen refresh: Re-triggers updateLimits() when connectivity state changes, so the "Available" field updates after coming back online
• IsOnlineTracker fix: Fixed isFirstEmission flag never being set to false, which prevented connectivity toasts from ever appearing
• LightningRepo.awaitPeerConnected(): New method that polls for peer reconnection (up to 30s) before attempting cooperative channel close — prevents "Cannot begin shutdown while peer is disconnected" errors during transfer to savings after internet toggle
• TransferViewModel.closeChannels(): Calls awaitPeerConnected() before attempting cooperative close, reducing unnecessary INTERRUPTED state in the savings progress screen

Preview

transfer-to-spending.webm

receive-sheet.webm

send-sheet.webm

transfer-to-savings.webm

QA Notes

Connection Issues Overlay

1. Open the Send Bitcoin sheet, toggle airplane mode on
   • Connection Issues overlay should fade in over the send flow
   • Title should read "Send Bitcoin"
   • Dashed yellow rings and phone illustration should be visible
   • Spinner should be animating at the bottom
2. Re-enable connectivity
   • Overlay should fade out
   • Send flow state should be preserved (no navigation reset)
3. Repeat for Receive Bitcoin sheet (title: "Receive Bitcoin")
4. Repeat for Force Transfer sheet (title: "Transfer Funds")
5. Repeat for Transfer to Spending screens (amount + confirm)
6. Repeat for Transfer to Savings confirm screen
7. Verify the overlay does not appear when connectivity is stable

Network Recovery — Send Flow

8. With on-chain + lightning balance, enable airplane mode → open send sheet → disable airplane mode → paste unified zero-amount invoice
   • Both savings AND spending options should appear (not just savings)

Network Recovery — Transfer to Savings

9. Toggle airplane mode off/on → immediately confirm transfer to savings
   • Progress screen should wait for peer reconnection and show SUCCESS (not INTERRUPTED)
   • Check logs for "Waiting for peer to reconnect" message

Connectivity Toasts

10. Toggle airplane mode on → "Internet Connectivity Issues" warning toast should appear
11. Toggle airplane mode off → "Internet Connection Restored" success toast should appear

[jvsena42]

@piotr-iohk I suppose there is a missing update in a test flow, because of the detail button

[ovitrif]

LightningRepo.canSend() fallback: When channels are loading (node Starting or channels not yet usable after reconnect), falls back to cached totalLightningSats balance instead of returning false — fixes unified invoices only showing savings option after reconnecting

And it if doesn't connect in time or the LN channels don't become usable for whatever reasions, it will show unified invoice which doesn't work because it's gonna fail when trying to send the LN sats.
Why not refactor it to use a flow?

Caching is not a silver bullet, on the contrary, it's usually the root of most issues in programming.

[jvsena42]

Tests after removing the cache and implement and implement await/asynchronous logic

zero-amount.webm

with-amount.webm

deeplink-and-quickpay.webm