Monero: fix decoy selection algo and add test for latest spendable (#384)

* Monero: fix decoy selection algo and add test for latest spendable

- DSA only selected coinbase outputs and didn't match the wallet2
implementation
- Added test to make sure DSA will select a decoy output from the
most recent unlocked block
- Made usage of "height" in DSA consistent with other usage of
"height" in Monero code (height == num blocks in chain)
- Rely on monerod RPC response for output's unlocked status

* xmr runner tests mine until outputs are unlocked

* fingerprintable canoncial select decoys

* Separate fingerprintable canonical function

Makes it simpler for callers who are unconcered with consistent
canonical output selection across multiple clients to rely on
the simpler Decoy::select and not worry about fingerprintable
canonical

* fix merge conflicts

* Put back TODO for issue #104

* Fix incorrect check on distribution len

The RingCT distribution on mainnet doesn't start until well after
genesis, so the distribution length is expected to be < height.

To be clear, this was my mistake from this series of changes
to the DSA. I noticed this mistake because the DSA would error
when running on mainnet.

coins/monero/src/lib.rs

@@ -46,6 +46,10 @@ pub mod wallet;
 #[cfg(test)]
 mod tests;
 
+pub const DEFAULT_LOCK_WINDOW: usize = 10;
+pub const COINBASE_LOCK_WINDOW: usize = 60;
+pub const BLOCK_TIME: usize = 120;
+
 static INV_EIGHT_CELL: OnceLock<Scalar> = OnceLock::new();
 #[allow(non_snake_case)]
 pub(crate) fn INV_EIGHT() -> Scalar {