Make sure to mention that step 2 is required in the guide.

`pq thread select t-x` doesn't work without running `pq profile info`
first. If the pq session is restarted in between, we need to call it
again to make sure that we generate the thread handles etc.

Author: canova

src/profile-query-cli/guide.txt

@@ -24,7 +24,7 @@ CORE WORKFLOW
     pq profile info --all    Show all processes and threads (not just top 5)
     pq profile info --search GeckoMain   Filter by process/thread name, pid, or tid
 
-  Step 3: Select a thread to analyze
+  Step 3: Select a thread to analyze (requires Step 2 -- profile info builds thread handles)
     pq thread select t-0     Select a specific thread (persists for future commands)
 
   Step 4: Analyze CPU usage