fixed pending share race error on warm app start

lib/share_intent/pending_share.dart

@@ -12,4 +12,17 @@ class PendingShare {
   bool get hasFiles => filePaths.isNotEmpty;
   bool get hasText => text != null && text!.isNotEmpty;
   bool get isEmpty => !hasFiles && !hasText;
+
+  /// True when [other] carries the same payload. The iOS Share Extension
+  /// fires two `open(url)` requests per share (see ShareViewController), so
+  /// the same share can arrive twice on the media stream — receivedAt is
+  /// deliberately ignored here so such duplicates compare equal.
+  bool contentEquals(PendingShare other) {
+    if (text != other.text) return false;
+    if (filePaths.length != other.filePaths.length) return false;
+    for (var i = 0; i < filePaths.length; i++) {
+      if (filePaths[i] != other.filePaths[i]) return false;
+    }
+    return true;
+  }
 }

lib/share_intent/share_intent_listener.dart

@@ -25,7 +25,7 @@ class ShareIntentListener {
     try {
       final initial = await ReceiveSharingIntent.instance.getInitialMedia();
       final share = _toPendingShare(initial);
-      if (share != null) pending.value = share;
+      if (share != null) _publish(share);
       await ReceiveSharingIntent.instance.reset();
     } catch (e) {
       debugPrint('ShareIntentListener.initialize failed: $e');
@@ -37,13 +37,24 @@ class ShareIntentListener {
     _streamSub ??= ReceiveSharingIntent.instance.getMediaStream().listen(
       (items) {
         final share = _toPendingShare(items);
-        if (share != null) pending.value = share;
+        if (share != null) _publish(share);
       },
       onError: (Object e) =>
           debugPrint('ShareIntentListener stream error: $e'),
     );
   }
 
+  /// The iOS Share Extension fires two `open(url)` requests per share, so the
+  /// same payload can arrive twice in quick succession. Publishing the
+  /// duplicate would re-trigger the share-flow navigation, pop the already
+  /// open ShareTargetPage and thereby delete the temp files of the share that
+  /// is still in flight — swallow it instead.
+  void _publish(PendingShare share) {
+    final current = pending.value;
+    if (current != null && current.contentEquals(share)) return;
+    pending.value = share;
+  }
+
   /// Cancels the warm-share subscription. The singleton survives, so a
   /// subsequent [attach] re-subscribes.
   void detach() {
@@ -53,8 +64,15 @@ class ShareIntentListener {
 
   /// Discards the current share and removes any temp files the plugin copied
   /// into the app cache. Idempotent.
-  void clear() {
+  ///
+  /// Pass [ifCurrent] from UI that owns a specific share (e.g. the
+  /// ShareTargetPage pop handler): the call then only acts while that share
+  /// is still the pending one. Without the guard, popping a stale share page
+  /// after a new share arrived would delete the new share's temp files before
+  /// its upload ran.
+  void clear({PendingShare? ifCurrent}) {
     final current = pending.value;
+    if (ifCurrent != null && !identical(current, ifCurrent)) return;
     pending.value = null;
     if (current != null) {
       for (final path in current.filePaths) {