- Window size/position remembered between sessions via SessionStore
- Step indicator dots now clickable to navigate directly to that step,
with keyboard shortcut hints in tooltips
- File list in add-files dialog shows format and size per image,
header shows total count and total size
- Welcome dialog now saves skill level choice to config
- SessionState extended with window_width, window_height, window_maximized
inotify-based folder watcher using the notify crate that detects new
image files, ignores non-image files, and supports start/stop lifecycle.
WatchFolder config struct for preset-linked watched directories.
Preset save/load/list/delete/import/export, config JSON persistence,
session state save/restore, and processing history log with append/clear.
All stored as JSON under ~/.config/pixstrip/.
ImageLoader: load image info (dimensions, format, file size) and pixels.
Discovery: find image files by extension, flat or recursive, single file or directory.
All 9 tests passing.
