v1.0.40: fix duplicate timer race condition on rapid double-press

onKeyDown is async and calls await startTimer (~1s network). A second
press before that resolves saw the same state (isRunning=false,
memRunningEntryId=null) and created a second Notion entry. Only the
last startTimer call's ID was tracked, orphaning the first entry
running indefinitely in Notion.

pendingKeyDown Set acts as a per-action mutex: a second press while the
first is in-flight is dropped. try/finally guarantees the lock is always
released.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/plugin.ts

@@ -1,4 +1,4 @@
-const CURRENT_VERSION = "1.0.39";
+const CURRENT_VERSION = "1.0.40";
 const GITEA_BASE = "https://gitea.pdmarf.co.uk/pdm/stream_deck_notion_timer/raw/branch/stable-rebuild";
 const SIGNING_PUBLIC_KEY = `-----BEGIN PUBLIC KEY-----
 MCowBQYDK2VwAyEAN7ko8TUpuPzPAJuKAZCRjV0c4ZSlou5d9pUAF6o12b4=
@@ -167,6 +167,7 @@ function buttonTitle(projectName: string): string {
 @action({ UUID: "com.pdma.notion-timer.toggle" })
 class TimerToggle extends SingletonAction<TimerSettings> {
   private projectCache = new Map<string, TimerSettings>();
+  private pendingKeyDown = new Set<string>();
 
   async onWillAppear(ev: WillAppearEvent<TimerSettings>): Promise<void> {
     this.projectCache.set(ev.action.id, ev.payload.settings);
@@ -185,6 +186,9 @@ class TimerToggle extends SingletonAction<TimerSettings> {
   }
 
   async onKeyDown(ev: KeyDownEvent<TimerSettings>): Promise<void> {
+    if (this.pendingKeyDown.has(ev.action.id)) return;
+    this.pendingKeyDown.add(ev.action.id);
+    try {
     const { projectId, projectName } = ev.payload.settings;
     const title = buttonTitle(projectName || "");
     const isRunning = memRunningActionId === ev.action.id;
@@ -231,6 +235,9 @@ class TimerToggle extends SingletonAction<TimerSettings> {
       streamDeck.logger.error("Timer toggle failed:", err);
       await ev.action.showAlert();
     }
+    } finally {
+      this.pendingKeyDown.delete(ev.action.id);
+    }
   }
 }