docs: move cursor rules to docs/, add project rules to CLAUDE.md

Also bump @uncaged/json-cas* to ^0.5.2

.cursor/rules/no-dynamic-import.mdc

@@ -1,27 +1,3 @@
----
-description: Ban dynamic import() in production code — use static imports instead
-globs: packages/*/src/**/*.ts
-alwaysApply: true
----
+# No Dynamic Import
 
-# No Dynamic Import in Production Code
-
-## Rule
-
-Do NOT use `await import()` or dynamic `import()` expressions in production source code.
-Always use static top-level `import` statements.
-
-## Exception (must include a comment explaining why)
-
-1. **Bundle loader** — loads user-authored workflow bundles whose paths are only known at runtime
-
-When suppressing, add a comment directly above:
-
-```ts
-// Dynamic import required: user bundle path resolved at runtime
-const mod = await import(bundlePath);
-```
-
-## Test Files
-
-Test files (`__tests__/**`) are exempt.
+See [docs/no-dynamic-import.md](../../docs/no-dynamic-import.md) for full rules.