[refactor] Simplify conditionals and improve method naming per review

- Combine nested conditions into single check for canvas change
- Use guard clauses to reduce nesting in rendering mode watch
- Rename start() to attemptStart() to better reflect that it may not actually start

src/components/graph/GraphCanvas.vue

@@ -303,17 +303,15 @@ watch(
     }
 
     // Canvas changed - restart sync
-    if (oldCanvas && oldCanvas !== canvas) {
-      if (slotSync && slotSyncStarted) {
-        slotSync.stop()
-        slotSyncStarted = false
-      }
+    if (oldCanvas && oldCanvas !== canvas && slotSync && slotSyncStarted) {
+      slotSync.stop()
+      slotSyncStarted = false
     }
 
     // Start sync if not in Vue mode and not already started
     if (!slotSync) slotSync = useSlotLayoutSync()
     if (!slotSyncStarted && !isVueNodesEnabled.value) {
-      const started = slotSync.start(canvas as LGraphCanvas)
+      const started = slotSync.attemptStart(canvas as LGraphCanvas)
       slotSyncStarted = started
     }
   },
@@ -334,16 +332,17 @@ watch(
         slotSyncStarted = false
       }
       // DOM will re-register via useDomSlotRegistration
-    } else {
-      // Switching TO LiteGraph
-      if (canvasStore.canvas && comfyApp.graph) {
-        // Ensure slot sync is active
-        if (!slotSync) slotSync = useSlotLayoutSync()
-        if (!slotSyncStarted) {
-          const started = slotSync.start(canvasStore.canvas as LGraphCanvas)
-          slotSyncStarted = started
-        }
-      }
+      return
+    }
+
+    // Switching TO LiteGraph
+    if (!canvasStore.canvas || !comfyApp.graph) return
+
+    // Ensure slot sync is active
+    if (!slotSync) slotSync = useSlotLayoutSync()
+    if (!slotSyncStarted) {
+      const started = slotSync.attemptStart(canvasStore.canvas as LGraphCanvas)
+      slotSyncStarted = started
     }
   },
   { immediate: false }

src/renderer/core/layout/sync/useSlotLayoutSync.ts

@@ -57,11 +57,11 @@ export function useSlotLayoutSync() {
   let restoreHandlers: (() => void) | null = null
 
   /**
-   * Start slot layout sync with full event-driven functionality
+   * Attempt to start slot layout sync with full event-driven functionality
    * @param canvas LiteGraph canvas instance
    * @returns true if sync was actually started, false if early-returned
    */
-  function start(canvas: LGraphCanvas): boolean {
+  function attemptStart(canvas: LGraphCanvas): boolean {
     // When Vue nodes are enabled, slot DOM registers exact positions.
     // Skip calculated registration to avoid conflicts.
     if (LiteGraph.vueNodesMode) {
@@ -160,7 +160,7 @@ export function useSlotLayoutSync() {
   })
 
   return {
-    start,
+    attemptStart,
     stop
   }
 }