Enhance post-webhook metadata handling

Added metadata refresh capability immediately after subtitle generation
when handling Plex webhooks. If subtitle generation is successful, the
Plex item's metadata is attempted to be refreshed to ensure that the
updates are reflected. The change includes robust error handling to log
failures in refreshing metadata and alerts the user if the webhook is
misconfigured. This enhancement improves the overall user experience by
ensuring the media library is up-to-date after any subtitle changes.

subgen/subgen.py

@@ -128,8 +128,13 @@ def receive_plex_webhook(
             logging.debug("Path of file: " + fullpath)
      
             gen_subtitles(path_mapping(fullpath), transcribe_or_translate, True)
-    else:
-        print("This doesn't appear to be a properly configured Plex webhook, please review the instructions again!")
+            try:
+                refresh_plex_metadata(item_id, plexserver, plextoken)
+                logging.info(f"Metadata for item {item_id} refreshed successfully.")
+            except Exception as e:
+                logging.error(f"Failed to refresh metadata for item {item_id}: {e}")
+            else:
+                print("This doesn't appear to be a properly configured Plex webhook, please review the instructions again!")
      
     return ""
 
@@ -355,6 +360,37 @@ def get_plex_file_name(itemid: str, server_ip: str, plex_token: str) -> str:
     else:
         raise Exception(f"Error: {response.status_code}")
 
+def refresh_plex_metadata(itemid: str, server_ip: str, plex_token: str) -> None:
+    """
+    Refreshes the metadata of a Plex library item.
+    
+    Args:
+        itemid: The ID of the item in the Plex library whose metadata needs to be refreshed.
+        server_ip: The IP address of the Plex server.
+        plex_token: The Plex token used for authentication.
+        
+    Raises:
+        Exception: If the server does not respond with a successful status code.
+    """
+
+    # Plex API endpoint to refresh metadata for a specific item
+    url = f"http://{server_ip}:32400/library/metadata/{itemid}/refresh"
+
+    # Headers to include the Plex token for authentication
+    headers = {
+        "X-Plex-Token": plex_token,
+    }
+
+    # Sending the PUT request to refresh metadata
+    response = requests.put(url, headers=headers)
+
+    # Check if the request was successful
+    if response.status_code == 200:
+        print("Metadata refresh initiated successfully.")
+    else:
+        raise Exception(f"Error refreshing metadata: {response.status_code}")
+
+
 def get_jellyfin_file_name(item_id: str, jellyfin_url: str, jellyfin_token: str) -> str:
     """Gets the full path to a file from the Jellyfin server.