When we intially implemented `bitcoind` syncing polling the mempool was
very frequent and rather inefficient so we made a choice not to
unnecessarily update the payment store for mempool changes, especially
since we only consider transactions `Succeeded` after
`ANTI_REORG_DELAY` anyways.

However, since then we made quite a few peformance improvements to the
mempool syncing, and by now we should just update they payment store as
not doing so will lead to rather unexpected behavior, making some tests
fail for `TestChainSource::Bitcoind`, e.g., `channel_full_cycle_0conf`,
which we fix here.

As we recently switched to updating the payment store based on BDK's
`WalletEvent`, but they currently don't offer an API returning such
events when applying mempool transactions, we copy over the respective
method for generating events from `bdk_wallet`, with the intention of
dropping it again once they do.

Signed-off-by: Elias Rohrer <[email protected]>

Previously, we fixed than a fresh node syncing via `bitcoind` RPC would
resync all chain data back to genesis. However, while introducing a
wallet birthday is great, it disallowed discovery of historical funds if
a wallet would be imported from seed. Here, we add a recovery mode flag
to the builder that explictly allows to re-enable resyncing from genesis
in such a scenario. Going forward, we intend to reuse that API for an
upcoming Lightning recoery flow, too.

Previously, we'd selectively insert the funding outputs into the onchain
wallet to later allow calculating `fees_paid` when creating payment
store entries (only for splicing mostly). However, this didn't always work, and we might for
example end up with a missing funding output (and hence would fall back
to `fees_paid: Some(0)`) if it was a counterparty-initiated channel and
we synced via `bitcoind` RPC.

Here, we fix this by tracking all LDK-registered `txids` in
`ChainSource` and then in the `Wallet`'s `Listen` implementation insert
all outputs of all registered transactions into the `Wallet`, ensuring
we'd always have sufficient data for `calculate_fee` available.

Thereby we also fix the `onchain_send_receive` test which previously
failed when using `TestChainSource::Bitcoind`.

Signed-off-by: Elias Rohrer <[email protected]>