feat: add audio playback support (MP3/WAV/FLAC) and fix attachment loading in creator posts

lib/backend/providers/pawchive_provider.dart

@@ -414,7 +414,15 @@ class PawchiveProvider
     }
     final attachments = json['attachments'];
     if (attachments is List) {
-      files.addAll(attachments.whereType<Map>().map(Map<String, dynamic>.from));
+      for (final att in attachments.whereType<Map>()) {
+        final m = Map<String, dynamic>.from(att);
+        final path = (m['path'] ?? '').toString();
+        if (path.isNotEmpty &&
+            files.any((existing) => (existing['path'] ?? '').toString() == path)) {
+          continue;
+        }
+        files.add(m);
+      }
     }
 
     // Support link-only posts where author uploaded files to cloud drives (MEGA, GDrive, etc.)
@@ -468,6 +476,17 @@ class PawchiveProvider
       ];
     }
 
+    // Determine if there is a cover illustration for the post
+    String? postCoverUrl;
+    for (final f in files) {
+      final p = (f['path'] ?? '').toString();
+      final n = (f['name'] ?? '').toString();
+      if (_isPhotoType('$n $p') && p.isNotEmpty) {
+        postCoverUrl = _thumbnailUrl(p);
+        break;
+      }
+    }
+
     var index = 0;
     return files
         .map((fileMap) {
@@ -475,18 +494,26 @@ class PawchiveProvider
           final fileName = (fileMap['name'] ?? '').toString();
           final previewOnly = fileMap['preview_only'] == true;
 
-          final previewUrl = _thumbnailUrl(rawPath);
+          final type = _fileType('$fileName $rawPath');
+          final isPhoto = _isPhotoType('$fileName $rawPath');
+
+          // img.pawchive.pw/thumbnail only generates thumbnails for images/gifs.
+          // Non-image files (audio, video, archive) return 404 from thumbnail server.
+          final previewUrl = isPhoto
+              ? _thumbnailUrl(rawPath)
+              : (postCoverUrl ?? '');
+
           final fileUrl = previewOnly
-              ? previewUrl
+              ? (isPhoto ? previewUrl : _fileDownloadUrl(rawPath, fileName))
               : _fileDownloadUrl(rawPath, fileName);
 
-          final type = _fileType('$fileName $rawPath');
           final stableId =
               '${query.service}:${query.artistId}:$postId:${index++}';
           final tags = [
             query.service,
             query.artistName,
             if (title.trim().isNotEmpty) title.trim(),
+            if (type == 'audio') 'audio',
           ];
 
           return Post(
@@ -600,24 +627,57 @@ class PawchiveProvider
   }
 
   String _fileType(String value) {
-    final lower = value.toLowerCase().split('?').first;
-    if (lower.endsWith('.webm') || lower.endsWith('.mp4') || lower.endsWith('.mov')) {
+    final lower = value.toLowerCase().split('?').first.trim();
+    if (lower.endsWith('.webm') ||
+        lower.endsWith('.mp4') ||
+        lower.endsWith('.mov') ||
+        lower.endsWith('.mkv') ||
+        lower.endsWith('.avi') ||
+        lower.endsWith('.flv') ||
+        lower.endsWith('.wmv') ||
+        lower.endsWith('.m4v') ||
+        lower.endsWith('.ts')) {
       return 'video';
     }
+    if (lower.endsWith('.mp3') ||
+        lower.endsWith('.m4a') ||
+        lower.endsWith('.wav') ||
+        lower.endsWith('.ogg') ||
+        lower.endsWith('.flac') ||
+        lower.endsWith('.aac') ||
+        lower.endsWith('.opus') ||
+        lower.endsWith('.wma')) {
+      return 'audio';
+    }
     if (lower.endsWith('.gif')) return 'gif';
     if (lower.endsWith('.swf')) return 'swf';
-    if (lower.endsWith('.zip') || lower.endsWith('.rar') || lower.endsWith('.7z')) {
+    if (lower.endsWith('.zip') ||
+        lower.endsWith('.rar') ||
+        lower.endsWith('.7z') ||
+        lower.endsWith('.tar') ||
+        lower.endsWith('.gz') ||
+        lower.endsWith('.pdf') ||
+        lower.endsWith('.txt')) {
       return 'archive';
     }
     if (lower.endsWith('.png') ||
         lower.endsWith('.jpg') ||
         lower.endsWith('.jpeg') ||
-        lower.endsWith('.webp')) {
+        lower.endsWith('.webp') ||
+        lower.endsWith('.avif') ||
+        lower.endsWith('.bmp') ||
+        lower.endsWith('.heic') ||
+        lower.endsWith('.tiff')) {
       return 'photo';
     }
     return 'unknown';
   }
 
+  bool _isPhotoType(String value) {
+    final type = _fileType(value);
+    return type == 'photo' || type == 'gif';
+  }
+
   DateTime? _dateFromAny(dynamic value) {
     if (value == null) return null;
     if (value is num) {