Get album info (when available) from Last.fm, add getAlbumInfo endpoint (#2061)

* lastfm album.getInfo, getAlbuminfo(2) endpoints

* ... for description and reduce not found log level

* address first comments

* return all images

* Update migration timestamp

* Handle a few edge cases

* Add CoverArtPriority option to retrieve albumart from external sources

* Make agents methods more descriptive

* Use Last.fm name consistently

Co-authored-by: Deluan <deluan@navidrome.org>

core/agents/lastfm/responses.go

@@ -4,6 +4,7 @@ type Response struct {
 	Artist         Artist         `json:"artist"`
 	SimilarArtists SimilarArtists `json:"similarartists"`
 	TopTracks      TopTracks      `json:"toptracks"`
+	Album          Album          `json:"album"`
 	Error          int            `json:"error"`
 	Message        string         `json:"message"`
 	Token          string         `json:"token"`
@@ -12,12 +13,20 @@ type Response struct {
 	Scrobbles      Scrobbles      `json:"scrobbles"`
 }
 
+type Album struct {
+	Name        string          `json:"name"`
+	MBID        string          `json:"mbid"`
+	URL         string          `json:"url"`
+	Image       []ExternalImage `json:"image"`
+	Description Description     `json:"wiki"`
+}
+
 type Artist struct {
-	Name  string        `json:"name"`
-	MBID  string        `json:"mbid"`
-	URL   string        `json:"url"`
-	Image []ArtistImage `json:"image"`
-	Bio   ArtistBio     `json:"bio"`
+	Name  string          `json:"name"`
+	MBID  string          `json:"mbid"`
+	URL   string          `json:"url"`
+	Image []ExternalImage `json:"image"`
+	Bio   Description     `json:"bio"`
 }
 
 type SimilarArtists struct {
@@ -29,12 +38,12 @@ type Attr struct {
 	Artist string `json:"artist"`
 }
 
-type ArtistImage struct {
+type ExternalImage struct {
 	URL  string `json:"#text"`
 	Size string `json:"size"`
 }
 
-type ArtistBio struct {
+type Description struct {
 	Published string `json:"published"`
 	Summary   string `json:"summary"`
 	Content   string `json:"content"`