stone pool renamed to constant pool - more appropriate

CLAUDE.md

@@ -113,6 +113,19 @@ var v = a[]   // pop: v is 3, a is [1, 2]
 - `packages/` — core packages
 - `Makefile` — build system (`make` to rebuild, `make bootstrap` for first build)
 
+## Testing
+
+After any C runtime changes, run all three test suites before considering the work done:
+
+```
+make                        # rebuild
+./cell --dev vm_suite       # VM-level tests (641 tests)
+./cell --dev test suite     # language-level tests (493 tests)
+./cell --dev fuzz           # fuzzer (100 iterations)
+```
+
+All three must pass with 0 failures.
+
 ## Documentation
 
 The `docs/` folder is the single source of truth. The website at `website/` mounts it via Hugo. Key files: