Improve effect propagation by skipping hooks in trackCall (#25940)

ref https://github.com/nim-lang/Nim/pull/25731
don't propagate effects for assignment hooks without effect lists

compiler/sempass2.nim

@@ -1197,7 +1197,9 @@ proc trackCall(tracked: PEffects; n: PNode) =
         else:
           if laxEffects notin tracked.c.config.legacyFeatures and a.kind == nkSym and
               a.sym.kind in routineKinds:
-            propagateEffects(tracked, n, a.sym)
+            let (isHook, opKind) = findHookKind(a.sym.name.s)
+            if (not isHook) or opKind notin {attachedAsgn, attachedSink, attachedDup}:
+              propagateEffects(tracked, n, a.sym)
       else:
         mergeRaises(tracked, effectList[exceptionEffects], n)
         mergeTags(tracked, effectList[tagEffects], n)

tests/effects/thooks.nim

@@ -13,4 +13,12 @@ proc send(x: string) =
   let wrapper = Thing(x: x)
   discard isolate(wrapper)
 
-send("la")
+send("la")
+
+block:
+  func enqueue[T](buf: var array[10, T], elem: sink T) =
+    `=sink`(buf[0], elem)
+
+  var buf: array[10, int]
+  enqueue(buf, 42)
+  assert buf[0] == 42