[WIP] Use native bits and registers for CircuitData.

crates/circuit/src/bit.rs

@@ -0,0 +1,25 @@
+use std::fmt::Debug;
+
+/// Keeps information about where a qubit is located within the circuit.
+#[derive(Debug, Clone, Copy, PartialEq, PartialOrd, Ord, Eq, Hash)]
+pub struct BitInfo {
+    register_idx: u32,
+    index: u32,
+}
+
+impl BitInfo {
+    pub fn new(register_idx: u32, index: u32) -> Self {
+        Self {
+            register_idx,
+            index,
+        }
+    }
+
+    pub fn register_index(&self) -> u32 {
+        self.register_idx
+    }
+
+    pub fn index(&self) -> u32 {
+        self.index
+    }
+}