feat: Add support for syncing playlists

Signed-off-by: SindreKjelsrud <sindre@kjelsrud.dev>

README.md

@@ -5,6 +5,7 @@ A native Rust application to sync songs and albums from your self-hosted Navidro
 ## Features
 
 - 🎵 Sync songs and albums from Navidrome
+- 🎼 Sync playlists from Navidrome (as M3U8 files)
 - 📱 Support for iPod stock OS
 - 🎸 Support for Rockbox firmware
 - 📊 Scrobble listening history to ListenBrainz
@@ -69,9 +70,15 @@ cargo run -- sync --album "Album Name"
 # Sync specific artist
 cargo run -- sync --artist "Artist Name"
 
+# Sync specific playlist only
+cargo run -- sync --playlist "Playlist Name"
+
 # List available albums
 cargo run -- list-albums
 
+# List available playlists
+cargo run -- list-playlists
+
 # Check iPod connection
 cargo run -- check
 
@@ -85,6 +92,28 @@ cargo run -- scrobble --clear
 cargo run -- scrobble --clear --no-backup
 ```
 
+### Syncing Playlists
+
+NaviPod can sync your Navidrome playlists to your iPod as M3U8 files:
+
+1. Enable playlist syncing in your `config.toml`:
+   ```toml
+   [sync]
+   playlists = true
+   ```
+2. Run the sync command:
+   ```bash
+   # Sync all playlists
+   cargo run -- sync
+   
+   # Or sync a specific playlist only
+   cargo run -- sync --playlist "My Favorites"
+   ```
+3. Playlists will be created in the `Playlists` folder on your iPod
+4. Only songs that are already on your iPod will be included in the playlists
+
+**Note:** Playlists use M3U8 format (UTF-8 encoded) with relative paths, which works with both Rockbox and most other media players.
+
 ### Scrobbling to ListenBrainz
 
 NaviPod can read the `.scrobbler.log` file from your Rockbox iPod and submit your listening history to ListenBrainz: