chore(core): Add preview notice to AI node SDK and CLI prompts (#26045)

Author: DawidMyslak

packages/@n8n/ai-node-sdk/README.md

@@ -1,5 +1,7 @@
 # @n8n/ai-node-sdk
 
+> **Preview:** This package is in preview. The API may change without notice. AI nodes are not yet accepted for verification.
+
 Public SDK for building AI nodes in n8n. This package provides a simplified API for creating chat model and memory nodes without LangChain dependencies.
 
 ## Installation in node packages

packages/@n8n/node-cli/src/commands/new/prompts.ts

@@ -58,12 +58,12 @@ export const programmaticNodeTypePrompt = async () =>
 					hint: 'Standard programmatic node',
 				},
 				{
-					label: 'Chat Model',
+					label: 'Chat Model (preview)',
 					value: 'chatModel',
 					hint: 'AI chat model node',
 				},
 				{
-					label: 'Chat Memory',
+					label: 'Chat Memory (preview)',
 					value: 'chatMemory',
 					hint: 'AI chat memory node',
 				},