Move, copy and Run work again from the JavaScript SDKs

Moving or copying a node from the browser or Node.js client sent the request under the wrong field names, and the server has no way to report that: it simply builds the request with empty paths and the operation completes having done nothing. The same silence hid a broken Run trigger, a partial update request that never identified the node it was meant to change, and a node subscription that could not be resolved.

The clients now send exactly the names the server declares, and a new check compares every field name against the server's own definitions on each build — so a future rename turns the build red instead of turning a feature into a no-op.