Fix getCachedPath to try file suffixes like resolveOrDownload

- getCachedPath now accepts suffixes parameter to try multiple extensions
- Pass suffixes from get_real_path to getCachedPath for consistent lookup
- Fixes issue where cached files with extensions weren't found

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: OmniTroid

src/path_functions.cpp

@@ -425,7 +425,7 @@ QString AOApplication::get_real_path(const VPath &vpath, const QStringList &suff
   // Check webcache if local file not found
   if (Options::getInstance().webcacheEnabled() && !m_serverdata.get_asset_url().isEmpty())
   {
-    QString cached = m_webcache->getCachedPath(vpath.toQString());
+    QString cached = m_webcache->getCachedPath(vpath.toQString(), suffixes);
     if (!cached.isEmpty())
     {
       asset_lookup_cache.insert(qHash(vpath), cached);

src/webcache.cpp

@@ -87,7 +87,7 @@ QString WebCache::cacheSubdir() const
   return subdir;
 }
 
-QString WebCache::getCachedPath(const QString &relativePath) const
+QString WebCache::getCachedPath(const QString &relativePath, const QStringList &suffixes) const
 {
   if (relativePath.isEmpty())
   {
@@ -100,21 +100,28 @@ QString WebCache::getCachedPath(const QString &relativePath) const
     return QString();
   }
 
-  // Use lowercase path for cache lookup (no percent-encoding in local paths)
-  QString lowerPath = lowercasePath(relativePath);
-  QString localPath = cacheDir() + subdir + lowerPath;
-
-  if (!file_exists(localPath))
+  // Try each suffix
+  QStringList effectiveSuffixes = suffixes.isEmpty() ? QStringList{""} : suffixes;
+  for (const QString &suffix : effectiveSuffixes)
   {
-    return QString();
-  }
+    // Use lowercase path for cache lookup (no percent-encoding in local paths)
+    QString lowerPath = lowercasePath(relativePath + suffix);
+    QString localPath = cacheDir() + subdir + lowerPath;
 
-  if (isExpired(localPath))
-  {
-    return QString();
+    if (!file_exists(localPath))
+    {
+      continue;
+    }
+
+    if (isExpired(localPath))
+    {
+      continue;
+    }
+
+    return localPath;
   }
 
-  return localPath;
+  return QString();
 }
 
 bool WebCache::isExpired(const QString &localPath) const

src/webcache.h

@@ -23,9 +23,10 @@ class WebCache : public QObject
   /**
    * @brief Returns the cached file path if it exists and is not expired.
    * @param relativePath The virtual path relative to the base (e.g., "sounds/music/song.mp3")
+   * @param suffixes List of file extensions to try (e.g., {".png", ".webp"})
    * @return The absolute path to the cached file, or empty string if not cached/expired.
    */
-  QString getCachedPath(const QString &relativePath) const;
+  QString getCachedPath(const QString &relativePath, const QStringList &suffixes = {""}) const;
 
   /**
    * @brief Check cache and initiate async download if file is missing or expired.