fix(scanner): ensure full scans update the DB (#4252)

* fix: ensure full scan refreshes all artist stats

After PR #4059, full scans were not forcing a refresh of all artists.
This change ensures that during full scans, all artist stats are refreshed
instead of only those with recently updated media files.

Changes:
- Set changesDetected=true at start of full scans to ensure maintenance operations run
- Add allArtists parameter to RefreshStats() method
- Pass fullScan state to RefreshStats to control refresh scope
- Update mock repository to match new interface

Fixes #4246
Related to PR #4059

* fix: add tests for full and incremental scans

Signed-off-by: Deluan <deluan@navidrome.org>

---------

Signed-off-by: Deluan <deluan@navidrome.org>

scanner/scanner.go

@@ -45,14 +45,25 @@ func (s *scanState) sendError(err error) {
 }
 
 func (s *scannerImpl) scanAll(ctx context.Context, fullScan bool, progress chan<- *ProgressInfo) {
-	state := scanState{progress: progress, fullScan: fullScan}
+	startTime := time.Now()
+
+	state := scanState{
+		progress:        progress,
+		fullScan:        fullScan,
+		changesDetected: atomic.Bool{},
+	}
+
+	// Set changesDetected to true for full scans to ensure all maintenance operations run
+	if fullScan {
+		state.changesDetected.Store(true)
+	}
+
 	libs, err := s.ds.Library(ctx).GetAll()
 	if err != nil {
 		state.sendWarning(fmt.Sprintf("getting libraries: %s", err))
 		return
 	}
 
-	startTime := time.Now()
 	log.Info(ctx, "Scanner: Starting scan", "fullScan", state.fullScan, "numLibraries", len(libs))
 
 	// Store scan type and start time
@@ -148,7 +159,7 @@ func (s *scannerImpl) runRefreshStats(ctx context.Context, state *scanState) fun
 			return nil
 		}
 		start := time.Now()
-		stats, err := s.ds.Artist(ctx).RefreshStats()
+		stats, err := s.ds.Artist(ctx).RefreshStats(state.fullScan)
 		if err != nil {
 			log.Error(ctx, "Scanner: Error refreshing artists stats", err)
 			return fmt.Errorf("refreshing artists stats: %w", err)