fix: merge duplicate click props + upgrade streaming examples

- Duplicate prop keys now merge into Block expressions
  click: a then click: b → Block([a, b])
- All actions fire in one click (was silently overwriting)
- streaming-mood.ds upgraded to semicolons
- streaming-stats.ds upgraded to semicolons
- Browser-verified: Happy button fires 3 actions (mood+color+energy)
- All 7 examples pass regression

compiler/ds-parser/src/parser.rs

@@ -1373,7 +1373,34 @@ impl Parser {
                 } else {
                     first
                 };
-                props.push((key, val));
+                // Merge duplicate keys: `click: a` then `click: b` → Block([a, b])
+                if let Some(existing) = props.iter_mut().find(|(k, _)| *k == key) {
+                    // Merge with existing value
+                    match &existing.1 {
+                        Expr::Block(exprs) => {
+                            let mut merged = exprs.clone();
+                            match val {
+                                Expr::Block(new_exprs) => merged.extend(new_exprs),
+                                other => merged.push(other),
+                            }
+                            existing.1 = Expr::Block(merged);
+                        }
+                        _ => {
+                            let prev = existing.1.clone();
+                            match val {
+                                Expr::Block(mut new_exprs) => {
+                                    new_exprs.insert(0, prev);
+                                    existing.1 = Expr::Block(new_exprs);
+                                }
+                                other => {
+                                    existing.1 = Expr::Block(vec![prev, other]);
+                                }
+                            }
+                        }
+                    }
+                } else {
+                    props.push((key, val));
+                }
                 self.skip_newlines();
                 if self.check(&TokenKind::Comma) {
                     self.advance();

examples/streaming-mood.ds

@@ -3,7 +3,7 @@
 -- Only mood, energy, color are exposed (clicks is internal).
 --
 -- Run with:
---   dreamstack stream examples/streaming-mood.ds --port 3004 --relay ws://localhost:9100/source/mood
+--   dreamstack stream examples/streaming-mood.ds --port 3004
 
 let mood = "neutral"
 let energy = 50
@@ -22,29 +22,12 @@ view mood_tracker =
     text "Energy: {energy}%"
     text "Color: {color}"
     row [
-      button "😄 Happy" {
+      button "😄 Happy" { click: mood = "happy"; color = "green"; energy += 10 }
-        click: mood = "happy"
+      button "😐 Neutral" { click: mood = "neutral"; color = "gray" }
-        click: color = "green"
+      button "😤 Angry" { click: mood = "angry"; color = "red"; energy -= 10 }
-        click: energy = energy + 10
-      }
-      button "😐 Neutral" {
-        click: mood = "neutral"
-        click: color = "gray"
-      }
-      button "😤 Angry" {
-        click: mood = "angry"
-        click: color = "red"
-        click: energy = energy - 10
-      }
     ]
     row [
-      button "☕ Caffeine" {
+      button "☕ Caffeine" { click: energy += 25; clicks += 1 }
-        click: energy = energy + 25
+      button "😴 Rest" { click: energy -= 15; clicks += 1 }
-        click: clicks += 1
-      }
-      button "😴 Rest" {
-        click: energy = energy - 15
-        click: clicks += 1
-      }
     ]
   ]

examples/streaming-stats.ds

@@ -22,23 +22,9 @@ view stats =
     text "Average: {average}"
     text "Max: {max}"
     row [
-      button "+5" {
+      button "+5" { click: total += 1; sum += 5 }
-        click: total += 1
+      button "+10" { click: total += 1; sum += 10 }
-        click: sum += 5
+      button "+25" { click: total += 1; sum += 25; max = 25 }
-      }
+      button "+50" { click: total += 1; sum += 50; max = 50 }
-      button "+10" {
-        click: total += 1
-        click: sum += 10
-      }
-      button "+25" {
-        click: total += 1
-        click: sum += 25
-        click: max = 25
-      }
-      button "+50" {
-        click: total += 1
-        click: sum += 50
-        click: max = 50
-      }
     ]
   ]