feat: add episode title provider and service interfaces

internal/domain/episodes.go

@@ -8,12 +8,21 @@ type EpisodeAvailability struct {
 	Titles map[int]string
 }
 
-type EpisodeAvailabilityProvider interface {
+type EpisodeProvider interface {
 	Name() string
 	ResolveEpisodeProviderID(ctx context.Context, animeID int, titleCandidates []string) (string, error)
+}
+
+type EpisodeAvailabilityProvider interface {
+	EpisodeProvider
 	GetEpisodeAvailabilityByProviderID(ctx context.Context, providerID string) (EpisodeAvailability, error)
 }
 
+type EpisodeTitleProvider interface {
+	EpisodeProvider
+	GetEpisodeTitlesByProviderID(ctx context.Context, providerID string) (map[int]string, error)
+}
+
 type CanonicalEpisode struct {
 	Number  int    `json:"number"`
 	Title   string `json:"title"`
@@ -41,3 +50,7 @@ type EpisodeService interface {
 	GetCanonicalEpisodes(ctx context.Context, anime Anime, forceRefresh bool) (CanonicalEpisodeList, error)
 	RefreshTrackedDue(ctx context.Context, limit int) error
 }
+
+type EpisodeTitleService interface {
+	EnrichEpisodeTitles(ctx context.Context, anime Anime) (CanonicalEpisodeList, error)
+}