Introduce an "audio_normalization" option across the app and implement normalization for audio-only downloads. Updates include: add config default (ConfigManager), new language strings, settings UI checkbox + help text and logic to auto-enable force-audio-format when normalization is enabled, and persist the setting. Pass the setting from main app to DownloadThread, and in the downloader force re-encoding to mp3 when necessary and append --postprocessor-args ExtractAudio:-af loudnorm=... to apply EBU R128 normalization. This ensures normalization works reliably (avoids ffmpeg stream-copy errors) and keeps the behavior scoped to ExtractAudio postprocessor.
Introduce a new filename_format setting and UI to control yt-dlp output templates. ConfigManager now includes a default filename_format (%(title)s_%(resolution)s.%(ext)s). The DownloadSettingsDialog exposes a text input and help text for the format and saves the value to ConfigManager. DownloadThread now accepts a filename_format argument and uses it when building output templates for single videos and playlists. YTSageApp reads the config and passes the filename format into the download thread. Added corresponding English language strings.
Initialize an error buffer and collect yt-dlp "ERROR:" output lines during direct command runs. When the process exits non‑zero, emit a more informative error using the last two captured error lines (falling back to the generic return-code message if none were captured). Also ensure the buffer is present before appending and keep the existing delay/cleanup flow.
Renamed 'src/core' to 'ytsage/core' and updated all internal imports to use relative paths. This improves package structure and ensures correct module resolution after the directory move.
oop7