Add images to STV doc page

en/src/user_manual/polls/stv/index.md

@@ -46,6 +46,8 @@ The quota is the number of votes a candidate needs to win a seat.
 
 Voters drag and drop candidates to rank them in order of preference:
 
+![](../../assets/stv-vote-in-progress.png)
+
 - **Rank 1** = most preferred candidate
 - **Rank 2** = second choice
 - Continue ranking as many candidates as desired
@@ -69,6 +71,7 @@ If a voter has ranked no remaining candidates, their ballot is "exhausted" and t
 ## Understanding results
 
 After the poll closes, results are displayed in several sections:
+![](../../assets/stv-results-summary.png)
 
 ### Method and quota
 
@@ -91,7 +94,7 @@ A summary table of the winners with five columns:
 If the count results in a tie — where eliminating any of the remaining candidates would change the outcome — those candidates are shown in a separate table rather than arbitrarily choosing a winner.
 
 ### Round-by-round details
-
+![](../../assets/stv-results.png)
 An expandable section showing the full counting process. Each row is a candidate and each column is a counting round, showing vote tallies at each stage:
 
 - **Green highlight** = elected in this round (reached the quota)