This ensures that the BackupProvider will be stopped as soon as the
struct is dropped and the imex progress error event is emitted. This
makes it easier to use and also makes sure that the ffi call
dc_backup_provider_unref() does not lead to dangling resources.
* deps: Update iroh, remove default-net patch
The released version of default-net is now sufficient and iroh makes
sure this dependency is recent enough.
* Update cargo-deny config
* Newer version of spin, previous has been yanked
async-smtp does not implement read buffering anymore
and expects library user to implement it.
To implement read buffer, we wrap streams into BufStream
instead of BufWriter.
When connection pool is organized as a stack,
it always returns most recently used connection.
Because each connection has its own page cache,
using the connection with fresh cache improves performance.
I commented out `oauth2::tests::test_oauth_from_mx`
because it requires network connection,
turned off the Wi-Fi and ran the tests.
Before the change, with a queue:
```
$ hyperfine "cargo test"
Benchmark 1: cargo test
Time (mean ± σ): 56.424 s ± 4.515 s [User: 183.181 s, System: 128.156 s]
Range (min … max): 52.123 s … 68.193 s 10 runs
```
With a stack:
```
$ hyperfine "cargo test"
Benchmark 1: cargo test
Time (mean ± σ): 29.887 s ± 1.377 s [User: 101.226 s, System: 45.573 s]
Range (min … max): 26.591 s … 31.010 s 10 runs
```
On version 1.107.1:
```
$ hyperfine "cargo test"
Benchmark 1: cargo test
Time (mean ± σ): 43.658 s ± 1.079 s [User: 202.582 s, System: 50.723 s]
Range (min … max): 41.531 s … 45.170 s 10 runs
```
This adds functionality to send and receive a backup over the network
using a QR code.
The sender or provider prepares the backup, sets up a server that
waits for clients. It provides a ticket in the form of a QR code
which contains connection and authentication information.
The receiver uses the QR code to connect to the provider and fetches
backup, restoring it locally.
