style(artwork): fix comment accuracy and budget; fingerprint ArtistImageFolder

Correct the inverted workerDeps.extGate comment, trim over-budget doc comments, and add conf.Server.ArtistImageFolder to the resolution fingerprint so an image-folder change re-resolves artist artwork.

core/artwork/housekeeping.go

@@ -26,8 +26,8 @@ var staleAbsentKinds = []string{"ar", "al", "pl", "ra"}
 // Fingerprint summarizes the config knobs that affect artwork resolution outcomes; a
 // change means previously resolved (or absent) state may no longer be correct.
 func Fingerprint() string {
-	raw := fmt.Sprintf("%s|%s|%s|%t|%s",
-		conf.Server.CoverArtPriority, conf.Server.ArtistArtPriority,
+	raw := fmt.Sprintf("%s|%s|%s|%s|%t|%s",
+		conf.Server.CoverArtPriority, conf.Server.ArtistArtPriority, conf.Server.ArtistImageFolder,
 		conf.Server.Agents, conf.Server.EnableExternalServices, consts.Version)
 	sum := md5.Sum([]byte(raw)) //nolint:gosec // fingerprint, not security-sensitive
 	return hex.EncodeToString(sum[:])

core/artwork/housekeeping_test.go

@@ -72,6 +72,13 @@ var _ = Describe("Housekeeping", func() {
 			f2 := Fingerprint()
 			Expect(f1).NotTo(Equal(f2))
 		})
+
+		It("changes when ArtistImageFolder changes", func() {
+			conf.Server.ArtistImageFolder = "/before"
+			f1 := Fingerprint()
+			conf.Server.ArtistImageFolder = "/after"
+			Expect(Fingerprint()).NotTo(Equal(f1))
+		})
 	})
 
 	Describe("Backfill", func() {

core/artwork/processor.go

@@ -31,8 +31,8 @@ const (
 // thumbnailSize is the max dimension fed to blurhash.
 const thumbnailSize = 128
 
-// workerDeps are the collaborators processItem needs; extGate is nil outside
-// tests, in which case resolveItem falls back to a plain passthrough.
+// workerDeps are the collaborators processItem needs; extGate is set by NewWorker in
+// production and nil only in tests, where resolveItem falls back to a plain passthrough.
 type workerDeps struct {
 	ds      model.DataStore
 	store   *ImageStore

core/artwork/worker_soak_test.go

@@ -19,10 +19,8 @@ import (
 // performance benchmark, so it favors a stable signal over raw speed.
 const soakCycles = 2200
 
-// TestWorkerSoak drives processItem across a mix of sources (folder, embedded
-// extraction, dangling refs) for many cycles, reading each acquired image back
-// through ImageStore.Open, and asserts goroutines/heap plateau instead of
-// growing unbounded. Skipped under -short.
+// TestWorkerSoak runs processItem over many cycles across a mix of sources, asserting
+// goroutines/heap plateau instead of growing unbounded (a leak guard). Skipped under -short.
 func TestWorkerSoak(t *testing.T) {
 	if testing.Short() {
 		t.Skip("skipping soak test in short mode")