ezqms-537: make thread header hidable (#4458)

Signed-off-by: Alexey Zinoviev <alexey.zinoviev@xored.com>

plugins/chunter-resources/src/components/threads/ThreadView.svelte

@@ -25,6 +25,7 @@
 
   export let _id: Ref<ActivityMessage>
   export let selectedMessageId: Ref<ActivityMessage> | undefined = undefined
+  export let showHeader: boolean = true
 
   const messageQuery = createQuery()
   const dispatch = createEventDispatcher()
@@ -43,6 +44,7 @@
   let content: HTMLDivElement | undefined = undefined
 </script>
 
+{#if showHeader}
   <div class="header">
     <div class="title"><Label label={chunter.string.Thread} /></div>
     <!-- svelte-ignore a11y-click-events-have-key-events -->
@@ -56,6 +58,7 @@
       <IconClose size="medium" />
     </div>
   </div>
+{/if}
 {#if message}
   <ThreadParentMessage {message} />