feat: Data transformation nodes and actions in Nodes Panel (#7760)

- Split Items List node into separate nodes per action
- Review node descriptions
- New icons
- New sections in subcategories

---------

Co-authored-by: Giulio Andreini <andreini@netseven.it>
Co-authored-by: Deborah <deborah@starfallprojects.co.uk>
Co-authored-by: Michael Kret <michael.k@radency.com>

packages/nodes-base/nodes/RssFeedRead/RssFeedRead.node.json

@@ -21,8 +21,5 @@
 				"url": "https://n8n.io/blog/why-i-chose-n8n-over-zapier-in-2020/"
 			}
 		]
-	},
-	"subcategories": {
-		"Core Nodes": ["Helpers"]
 	}
 }