ui Prevent tool messages from incorrectly appending to other conversations (#25177)

* fix: Prevent tool messages from incorrectly appending to other conversations

* ui: prevent agentic loop from poisoning another conv's currNode

* ui: make editedContent a  so background recompute does not wipe in-progress edits

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Co-authored-by: Pascal <admin@serveurperso.com>

tools/ui/src/lib/components/app/chat/ChatMessages/ChatMessage/ChatMessage.svelte

@@ -43,7 +43,7 @@
 		assistantMessages: number;
 		messageTypes: string[];
 	} | null>(null);
-	let editedContent = $derived(message.content);
+	let editedContent = $state(message.content);
 
 	let rawEditContent = $derived.by(() => {
 		if (message.role !== MessageRole.ASSISTANT) return undefined;