platform.api in the Node.js engine fails silently when arguments are in the wrong position. Reproduced on 7.7.0 (df-script dev-develop 4fa09c4).

Repro (Node scripted service, local echo server as target):

// bug form: callback passed in the 3rd (options) slot, like get()
platform.api.delete(path, {marker: 'v1'}, function (body) { /* never runs */ });
// correct forms
platform.api.delete(path, {marker: 'v2'}, {}, function (body) { /* runs */ });
platform.api.delete(path, null, {}, function (body) { /* runs, true DELETE */ });

Observed (bug form):

• The callback never fires. No error is thrown or logged.
• The request is sent as POST with x-http-method: DELETE (truthy payload path, src/Engines/NodeJs.php ~243).
• The callback function is serialized into a bogus headers request header, and the payload body is empty.

Cause: get(path, options, callback) vs post/put/patch/delete(path, payload, options, callback). Called get-style, callback is undefined and http.request(_options, undefined) attaches no response handler.

Fix:

• In _platform.api.call (and the verb wrappers), throw a clear error when callback is not a function, naming the expected signature, e.g. platform.api.delete(path, payload, options, callback): callback must be a function.
• Do not serialize non-object options into headers.
• Same check for the Python engines' get vs write-verb split where it applies.

Docs side: dreamfactorysoftware/df-docs#130.