fix(cli-run): deduplicate tool headers and message counter resets on repeated events

Guard against duplicate tool header/output rendering when both tool.execute
and message.part.updated fire for the same tool, and prevent message counter
resets when message.updated fires multiple times for the same assistant message.

🤖 Generated with [OhMyOpenCode](https://github.com/code-yeongyu/oh-my-opencode) assistance

src/cli/run/event-state.ts

@@ -37,6 +37,8 @@ export interface EventState {
   textAtLineStart: boolean
   /** Whether reasoning stream is currently at line start (for padding) */
   thinkingAtLineStart: boolean
+  /** Current assistant message ID — prevents counter resets on repeated message.updated for same message */
+  currentMessageId: string | null
 }
 
 export function createEventState(): EventState {
@@ -63,5 +65,6 @@ export function createEventState(): EventState {
     lastThinkingSummary: "",
     textAtLineStart: true,
     thinkingAtLineStart: false,
+    currentMessageId: null,
   }
 }