fix(files): stop the embedded chat view being collaborative (streaming regressions)

Making the embedded /chat resource FileViewer collaborative (#6095) violated
the editor's core invariant that collaboration and agent-streaming are disjoint
surfaces (rich-markdown-editor.tsx: 'collaboration is enabled only on the Files
page, which never streams'). The embedded view IS a streaming surface, so this
caused three regressions:

- Copilot streaming into a settled md file showed only an initial chunk and did
  not stream live: collaborationEnabled latches true at mount, so the streaming
  reconcile loop early-returns and streamingContent is never applied. (A refresh
  mid-stream works because streamingAtMountRef is then true and collab is off.)
- The editor stayed read-only after a stream: isEditable gates on collabReady
  (synced+seeded), and the seed races the copilot write, so readiness can never
  land.
- Files loaded slower: collab files render empty and block on a socket->seed
  round-trip, discarding the already-fetched markdown.

Revert the embedded view to non-collaborative, restoring the disjoint-surfaces
invariant. The embedded /chat panel is a copilot streaming/preview surface, not
a multi-user collaborative one; the two-window live-caret case #6095 targeted
never worked in a single tab anyway (Files and chat are separate routes). The
Files-page collaborative editor is unchanged.

Author: waleedlatif1

apps/sim/app/workspace/[workspaceId]/home/components/mothership-view/components/resource-content/resource-content.tsx

@@ -720,7 +720,6 @@ function EmbeddedFile({
         streamIsIncremental={streamIsIncremental}
         disableStreamingAutoScroll={disableStreamingAutoScroll}
         previewContextKey={previewContextKey}
-        collaborative
       />
     </div>
   )