JCLCheck command palette commands missing category

Hi, I would expect there to be a category defined in front of each of these commands and the "Snippets" category name is misleading as it is actually in the JCL Check extension not in one called "Snippets" (this may be confusing as other extensions also provide snippets). E.g. `JCL Check: Insert Snippet` and `JCL Check; Check your JCL`


Start by locating the JCL Check extension's command palette command definitions and review the labels shown for the commands in the issue. Update the missing or misleading categories so each command is clearly identified as belonging to JCL Check, then verify the resulting command palette entries.

Written by the indexing model from the issue text.