Add scrobbling support (Last.fm + ListenBrainz) and rsp settings reload

- Full Last.fm API implementation with MD5 signing (track.updateNowPlaying, track.scrobble)
- Full ListenBrainz API implementation (/1/submit-listens for playing_now and single)
- ScrobbleState in daemon tracking track, start time, and unix timestamp per play
- Scrobble threshold: ≥30s play AND (≥half duration OR ≥4 min)
- Duration extraction from symphonia codec params into AudioMetadata and Track
- Token validation at daemon startup and on config change
- ListenBrainz token valid (user: Salmonium) command to re-read config from disk (avoids token in shell history)
- Desktop notifications for token validation results
- Empty-credential filtering (empty string = no-op)

1 files changed, 23 insertions, 25 deletions

diff --git a/tests/scrobbler.rs b/tests/scrobbler.rs
index f326250..5453748 100644
--- a/tests/scrobbler.rs
+++ b/tests/scrobbler.rs
@@ -24,54 +24,52 @@ fn test_scrobbler_new_with_none() {
 }
 
 #[test]
-fn test_scrobbler_now_playing_no_api_key() {
+fn test_scrobbler_now_playing_no_creds() {
     let scrobbler = Scrobbler::new(None, None, None, None);
     scrobbler.now_playing("Artist", "Track", Some("Album"));
 }
 
 #[test]
-fn test_scrobbler_now_playing_with_api_key() {
+fn test_scrobbler_now_playing_partial_lastfm() {
+    // Only api_key set — not enough to trigger Last.fm (needs secret + session_key too)
     let scrobbler = Scrobbler::new(Some("api_key".to_string()), None, None, None);
     scrobbler.now_playing("Artist", "Track", Some("Album"));
 }
 
 #[test]
-fn test_scrobbler_scrobble_no_keys() {
-    let scrobbler = Scrobbler::new(None, None, None, None);
-    scrobbler.scrobble("Artist", "Track", Some("Album"), 1234567890);
-}
-
-#[test]
-fn test_scrobbler_scrobble_with_lastfm() {
+fn test_scrobbler_now_playing_no_album() {
     let scrobbler = Scrobbler::new(Some("api_key".to_string()), None, None, None);
-    scrobbler.scrobble("Artist", "Track", Some("Album"), 1234567890);
+    scrobbler.now_playing("Artist", "Track", None);
 }
 
 #[test]
-fn test_scrobbler_scrobble_with_listenbrainz() {
-    let scrobbler = Scrobbler::new(None, None, None, Some("token".to_string()));
+fn test_scrobbler_scrobble_no_creds() {
+    let scrobbler = Scrobbler::new(None, None, None, None);
     scrobbler.scrobble("Artist", "Track", Some("Album"), 1234567890);
 }
 
 #[test]
-fn test_scrobbler_scrobble_with_both() {
-    let scrobbler = Scrobbler::new(
-        Some("api_key".to_string()),
-        None,
-        None,
-        Some("token".to_string()),
-    );
-    scrobbler.scrobble("Artist", "Track", Some("Album"), 1234567890);
+fn test_scrobbler_scrobble_no_album() {
+    let scrobbler = Scrobbler::new(None, None, None, None);
+    scrobbler.scrobble("Artist", "Track", None, 1234567890);
 }
 
 #[test]
-fn test_scrobbler_now_playing_no_album() {
+fn test_scrobbler_scrobble_partial_lastfm() {
+    // Only api_key set — not enough to trigger Last.fm
     let scrobbler = Scrobbler::new(Some("api_key".to_string()), None, None, None);
-    scrobbler.now_playing("Artist", "Track", None);
+    scrobbler.scrobble("Artist", "Track", Some("Album"), 1234567890);
 }
 
 #[test]
-fn test_scrobbler_scrobble_no_album() {
-    let scrobbler = Scrobbler::new(Some("api_key".to_string()), None, None, None);
-    scrobbler.scrobble("Artist", "Track", None, 1234567890);
+fn test_scrobbler_skip_empty_credentials() {
+    // Empty strings should be treated as unset — no HTTP requests
+    let scrobbler = Scrobbler::new(
+        Some("".to_string()),
+        Some("".to_string()),
+        Some("".to_string()),
+        Some("".to_string()),
+    );
+    scrobbler.now_playing("Artist", "Track", Some("Album"));
+    scrobbler.scrobble("Artist", "Track", Some("Album"), 1234567890);
 }