Devices no longer implicitely use the From address of sync messages
to determine their primary transport. Receivers have no concept of it and own devices
may disagree on which relay is reachable because of VPN or different networks:
1. Make setting a primary transport (`configured_addr`) a per-device non-synced operation.
2. Transport rows (add/remove/unpublish) keep syncing like before.
3. A device reelects a primary if a sync message unpublished/removed the current primary
if there is a better candidate.
4. `TransportsModified` event is emitted at most once on an incoming transport sync message.
Users will notice the change in that changing primary transport in settings/advanced/relays
will not synchronize to other devices anymore.
Fix https://github.com/chatmail/core/issues/7835.
The problem was most probably:
- `ac1_clone` receives the sync message, sends `TRANSPORTS_MODIFIED`
event, and launches a task that will restart IO
- After IO was stopped, but before it is started again,
`ac1_clone.add_transport_from_qr(qr)` is called
- this check fails:
```rust
ensure!(
!self.scheduler.is_running().await,
"cannot configure, already running"
);
```
This fixes the bug when a new transport doesn't become primary on the 2nd device because INBOX from
the new transport isn't fully fetched. Now the `Transports` sync message is received from the old
transport, but as it has updated "From", it updates the primary transport correspondingly. NB: I/O
for the new primary transport isn't immediately started however, this needs a separate fix.
Fix get_secondary_addrs() which was using
`secondary_addrs` config that is not updated anymore.
Instead of using `secondary_addrs` config,
use the `transports` table which contains all the addresses.
