Changes to Properties/Info button:
- Icon changed from document-properties to dialog-information (more intuitive)
- Tooltip updated to "Show in Finder Info"
- Button now opens native macOS Get Info window via AppleScript
- Extracted build_selection_info() helper function for reusability
Auto-display selection info in status bar:
- Selection info (name, size, item count) now auto-displays when items are selected
- Info updates automatically when selection changes
- Info clears when selection is removed
- Other messages (errors, navigation) can still interrupt and auto-dismiss after 5s
- Selection info remains persistent until selection changes
- Open in Finder button now always enabled and defaults to opening current directory when no selection exists
- Added sniffly_show_error() function that displays error messages for 5 seconds then auto-dismisses
- Imported g_timeout_add_seconds_once from GLib for timeout functionality
- Updated all error messages to use auto-dismiss feature (navigation errors, clipboard failures, etc.)
