Split out crypto$ derivs into separate type set

For crypto derivatives (at least futes), yes they are margined, but
generally not around a single unit of vlm (like equities or commodities
futes) so don't pre-set the order mode allocator to use a #unit limit,
$limit is fine.

piker/accounting/_mktinfo.py

@@ -48,12 +48,15 @@ _underlyings: list[str] = [
     'commodity',
 ]
 
+_crypto_derivs: list[str] = [
+    'perpetual_future',
+    'crypto_future',
+]
 
 _derivs: list[str] = [
     'swap',
     'future',
     'continuous_future',
-    'perpetual_future',
     'option',
     'futures_option',
 
@@ -68,6 +71,8 @@ AssetTypeName: Literal[
     _underlyings
     +
     _derivs
+    +
+    _crypto_derivs
 ]
 
 # egs. stock, futer, option, bond etc.