remove built-in Spotify integration (#5197)

* refactor: remove built-in Spotify integration

Remove the Spotify adapter and all related configuration, replacing
the built-in integration with the plugin system. This deletes the
adapters/spotify package, removes Spotify config options (ID/Secret),
updates the default agents list from "deezer,lastfm,spotify" to
"deezer,lastfm", and cleans up all references across configuration,
metrics, logging, artwork caching, and documentation. Users with
Spotify config options will now see a warning that the options are
no longer available.

* feat: add ListenBrainz to list of default agents

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

---------

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

plugins/examples/wikimedia/README.md

@@ -63,7 +63,7 @@ Folder = "/path/to/navidrome/plugins"
 Add the plugin to your agents list:
 
 ```toml
-Agents = "lastfm,spotify,wikimedia"
+Agents = "lastfm,wikimedia"
 ```
 
 ## Testing with Extism CLI

plugins/manifest-schema.json

@@ -149,7 +149,7 @@
         },
         "requiredHosts": {
           "type": "array",
-          "description": "List of required host patterns for HTTP requests (e.g., 'api.example.com', '*.spotify.com')",
+          "description": "List of required host patterns for HTTP requests (e.g., 'api.example.com', '*.musicbrainz.org')",
           "items": {
             "type": "string"
           }
@@ -189,7 +189,7 @@
         },
         "requiredHosts": {
           "type": "array",
-          "description": "List of required host patterns for WebSocket connections (e.g., 'api.example.com', '*.spotify.com')",
+          "description": "List of required host patterns for WebSocket connections (e.g., 'api.example.com', '*.musicbrainz.org')",
           "items": {
             "type": "string"
           }

plugins/manifest_gen.go

@@ -57,7 +57,7 @@ type HTTPPermission struct {
 	Reason *string `json:"reason,omitempty" yaml:"reason,omitempty" mapstructure:"reason,omitempty"`
 
 	// List of required host patterns for HTTP requests (e.g., 'api.example.com',
-	// '*.spotify.com')
+	// '*.musicbrainz.org')
 	RequiredHosts []string `json:"requiredHosts,omitempty" yaml:"requiredHosts,omitempty" mapstructure:"requiredHosts,omitempty"`
 }
 
@@ -251,6 +251,6 @@ type WebSocketPermission struct {
 	Reason *string `json:"reason,omitempty" yaml:"reason,omitempty" mapstructure:"reason,omitempty"`
 
 	// List of required host patterns for WebSocket connections (e.g.,
-	// 'api.example.com', '*.spotify.com')
+	// 'api.example.com', '*.musicbrainz.org')
 	RequiredHosts []string `json:"requiredHosts,omitempty" yaml:"requiredHosts,omitempty" mapstructure:"requiredHosts,omitempty"`
 }

plugins/manifest_test.go

@@ -19,7 +19,7 @@ var _ = Describe("Manifest", func() {
 				"permissions": {
 					"http": {
 						"reason": "Fetch metadata",
-						"requiredHosts": ["api.example.com", "*.spotify.com"]
+						"requiredHosts": ["api.example.com", "*.musicbrainz.org"]
 					}
 				}
 			}`)
@@ -34,7 +34,7 @@ var _ = Describe("Manifest", func() {
 			Expect(*m.Website).To(Equal("https://example.com"))
 			Expect(m.Permissions.Http).ToNot(BeNil())
 			Expect(*m.Permissions.Http.Reason).To(Equal("Fetch metadata"))
-			Expect(m.Permissions.Http.RequiredHosts).To(ContainElements("api.example.com", "*.spotify.com"))
+			Expect(m.Permissions.Http.RequiredHosts).To(ContainElements("api.example.com", "*.musicbrainz.org"))
 		})
 
 		It("parses a minimal manifest", func() {