update claude settings and wip DAG with SlotMap

.claude/memory/MEMORY.md

@@ -0,0 +1,5 @@
+# Memory Index
+
+- [No constant leaf in RcCircuit](feedback_dag_no_const_leaf.md) — coefficients live in Poly; don't suggest a Const variant for RcCircuit
+- [Always ask before changing settings](feedback_settings_approval.md) — describe proposed settings changes and wait for approval before editing any settings file
+- [Use cargo add for dependencies](feedback_cargo_add.md) — never edit Cargo.toml directly; use `cargo add <dep>` instead