This commit changes how we transform from a deadline option to a
concrete deadline value - previously this is done when we decide to
cluster inputs, and we now move it to a step earlier - once an input is
received via `SweeperInput`, we will immediately transform its optional
deadline into a real value. For inputs that come with a deadline option,
since the Some will be used, it makes no difference. For inputs with
None as their deadlines, we need this change to make sure the default
deadlines are assigned accurately.
This commit changes the method `ClusterInputs` to also take a default
deadline height. Previously, when calculating the default deadline
height for a non-time sensitive input, we would first cluster it with
other non-time sensitive inputs, then give it a deadline before we are
about to `sweep`. This is now moved to the step where we decide to
cluster inputs, allowing time-sensitive and non-sensitive inputs to be
grouped together, if they happen to share the same deadline heights.
This commit exports and renames the following variable names:
- `PendingInput` is now `PendingInputResponse` as it's responding to a
request.
- `pendingInput` is now renamed and exported as `SweeperInput`.
- `pendingInputs` is now renamed and exported as `InputsMap`.
This commit is first made from running:
```
gofmt -d -w -r 'PendingInput -> PendingInputResponse' .
gofmt -d -w -r 'pendingInput -> SweeperInput' .
gofmt -d -w -r 'pendingInputs -> InputsMap' .
```
And followed by some docs and variable names fixes.
This commit adds `BudgetAggregator` as a new implementation of
`UtxoAggregator`. This aggregator will group inputs by their deadline
heights and create input sets that can be used directly by the fee
bumper for fee calculations.
This commit makes the `ClusterInputs` directly returning the `InputSet`
so the sweeper doesn't know about the existence of `Cluster` interface.
This way we can have a deeper interface as the sweeper only needs to
interact with `Aggregator` only to get the final input sets, leaving the
implementation details being managed by `SimpleAggregator` and future
aggregators.
This commit refactors the grouping logic into a new interface
`UtxoAggregator`, which makes it easier to write tests and opens
possibility for future customized clustering strategies.
The old clustering logic is kept as and moved into `SimpleAggregator`.
