This ensures that files cannot appear on the remote destination, despite terminating the host program.
This fixes#4485
There is still work needed to handle the repair and compact operations so they use transactions and can commit changes during transfer progress.
This moves the throttle support to the StreamUtil throttled stream, which allows multiple streams to share a throttle value, such that the throttle setting is applied to the entire communication from Duplicati, and not for each connection.
This also cleans up a bit in the progress reporting, where the backend manager now keeps track of the "active" transfer and only emits progress on that. Once it finishes, a new transfer is promoted a "active".
* Rewrite the backend manager.
This creates a new more logic backend manager that handles all backend operations.
For each top-level operation, there is now a single backend manager instance that is passed to sub-commands.
The internals of the backend manager are now rewritten to use async logic instead of threading.
The design uses a single task runner that dispatches operations and honors concurrent settings and limits from one place.
The logic for each operation has been moved into a separate files/classes to make it easier to understand each operation.
This fixes#5804
* Fixed a few issues with not awaiting tasks
* Fixed not creating empty databases
* Fixed an issue with hashes not being recorded on download
* Reworked the download logic to avoid attempting to decrypt the file if it has been modified.
* Review fixes
* Renamed db collector to better reflect the purpose.
* Review fixes
Carl Johnsen