tree leaves are now editable. cleaning. removing redefine, since i can just eval() with :=

src/runtime-js.ts

@@ -113,12 +113,12 @@ export const _rt = {
         }
         syncToAst(name);
     },
-    redefine: (name: string) => (code: string) => {
-        const tokens = tokenize(`_tmp = ${code};`);
-        const parser = new Parser(tokens, "");
-        const defs = parser.parse();
-        recompile(name, defs[0].body);
-        return { _tag: 'Ok' };
+    rebindAt: (pathStr: string) => (value: string) => {
+        const parts = pathStr.split('.');
+        const name = parts[0];
+        const path = parts.slice(1);
+
+        return { _tag: 'Rebind', _0: name, _1: path, _2: value };
     },
     undefine: (name: string) => {
         delete store[name];