If you do not wish to restrict which REST methods and factories are accessible, deinstall the "rest_webservice_resources_to_expose" option. You can locate this option within the SDM web UI > Administration tab > Options Manager > Web Service section. Alternatively, you can search for the option by name, or can search for "rest%" to find it more easily.
Once the option is deinstalled, restart Service Desk Manager for the option to be effective.
If you would prefer to restrict the available methods and factories, you will need to configure this option by providing a comma-separated list of REST methods that should be made available. If advanced logging has been enabled on REST, jrest.log will contain multiple lines with the phrase "Constructor: factory" - searching the file for all lines that contain "Constructor: factory" will yield a list of all available factories.
After making either change above, you will need to run the pdm_rest_util -undeploy and pdm_rest_util -deploy commands again so that your changes will take effect.
After this issue has been resolved, caisd-rest.war should be approximately 4.5MB in size, and REST calls should function as normal. If you have it enabled, debug-level logging on jrest.log should look like the highlighted lines in the following image:
Note: For most factories, it's okay and expected to have the line "Skipping DELETE method", as deleting items is generally unsupported across Service Desk Manager as a whole.