computer: stateful: maybe got rollback to work, tbd

crates/brk_computer/examples/price_to_amount.rs

@@ -0,0 +1,15 @@
+use std::path::Path;
+
+use brk_computer::PriceToAmount;
+use brk_error::Result;
+use brk_structs::Height;
+
+pub fn main() -> Result<()> {
+    let path = Path::new(&std::env::var("HOME").unwrap())
+        .join(".brk")
+        .join("computed/stateful/states");
+    let mut price_to_amount = PriceToAmount::create(&path, "addrs_above_1btc_under_10btc");
+    dbg!(price_to_amount.import_at_or_before(Height::new(890000))?);
+    dbg!(price_to_amount);
+    Ok(())
+}