feat: import with verification, and a Wanted view of its own (M502 #5522)

A finished download is checked against MusicBrainz before anything is
filed: the files are paired with an edition's tracks by position or path,
and AcoustID, tag ids, lengths and titles say whether it is the album.
What is the album is copied into the library as
Artist/Album (Year)/Artist - Album - NN - Title, tagged with Picard's
MusicBrainz ids, and scanned; the download keeps seeding. What is not is
refused: set aside, removed from the client, and the album searched for
again. A download the check cannot settle waits for a person, who imports
it anyway or refuses it. Tracks the library already holds are skipped.

The wanted list leaves Admin for a top-level Wanted view, admin-only and
web-only, with tabs for Wanted, Activity (downloads and their imports,
the ones needing a person first), Missing files, Held, Following (with the
release-type profiles, moved off Integrations) and Blocked. The search
settings gain "File new music into" when the library has several folders.

The search pass logs why each failed search failed.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

internal/api/admin_wanted.go

@@ -49,11 +49,21 @@ type wantSearchView struct {
 	Error       string `json:"error"`
 }
 
+// wantGrabView is the want's latest download, running or ended, and what
+// its import made of it (#5522).
 type wantGrabView struct {
-	Name      string `json:"name"`
-	GrabbedAt string `json:"grabbed_at"`
-	Origin    string `json:"origin"`
-	Quality   string `json:"quality"`
+	ID            string  `json:"id"`
+	Name          string  `json:"name"`
+	GrabbedAt     string  `json:"grabbed_at"`
+	Origin        string  `json:"origin"`
+	Quality       string  `json:"quality"`
+	Live          bool    `json:"live"`
+	EndReason     string  `json:"end_reason"`
+	Progress      float32 `json:"progress"`
+	ImportState   string  `json:"import_state"`
+	ImportReason  string  `json:"import_reason"`
+	ImportedAt    *string `json:"imported_at"`
+	ImportedFiles int32   `json:"imported_files"`
 }
 
 // wantCounts sizes each tab of the Wanted page.
@@ -62,6 +72,11 @@ type wantCounts struct {
 	Missing   int64 `json:"missing"`
 	Held      int64 `json:"held"`
 	Following int64 `json:"following"`
+	// Activity: downloads running; Attention: of those, the ones waiting on
+	// a person; Blocked: releases set aside (#5522).
+	Activity  int64 `json:"activity"`
+	Attention int64 `json:"attention"`
+	Blocked   int64 `json:"blocked"`
 }
 
 type wantsPage struct {
@@ -102,7 +117,8 @@ func (h *handlers) handleListWants(w http.ResponseWriter, r *http.Request) {
 	}
 	out := wantsPage{
 		Items: make([]wantView, 0, len(rows)), Limit: wantsPageSize, Offset: offset,
-		Counts: wantCounts{Wanted: counts.Wanted, Missing: counts.Missing, Held: counts.Held, Following: counts.Following},
+		Counts: wantCounts{Wanted: counts.Wanted, Missing: counts.Missing, Held: counts.Held, Following: counts.Following,
+			Activity: counts.Activity, Attention: counts.Attention, Blocked: counts.Blocked},
 	}
 	switch state {
 	case "missing":
@@ -145,12 +161,19 @@ func (h *handlers) handleListWants(w http.ResponseWriter, r *http.Request) {
 			}
 		}
 		if row.GrabName != nil {
-			v.Grab = &wantGrabView{Name: *row.GrabName, GrabbedAt: formatTimestamp(row.GrabbedAt)}
-			if row.GrabOrigin != nil {
-				v.Grab.Origin = *row.GrabOrigin
+			v.Grab = &wantGrabView{ID: uuidToString(row.GrabID), Name: *row.GrabName,
+				GrabbedAt: formatTimestamp(row.GrabbedAt), Live: !row.GrabEndedAt.Valid,
+				Origin: deref(row.GrabOrigin), Quality: deref(row.GrabQuality), EndReason: deref(row.GrabEndReason),
+				ImportState: deref(row.GrabImportState), ImportReason: deref(row.GrabImportReason)}
+			if row.GrabProgress != nil {
+				v.Grab.Progress = *row.GrabProgress
 			}
-			if row.GrabQuality != nil {
-				v.Grab.Quality = *row.GrabQuality
+			if row.GrabImportedFiles != nil {
+				v.Grab.ImportedFiles = *row.GrabImportedFiles
+			}
+			if row.GrabImportedAt.Valid {
+				at := formatTimestamp(row.GrabImportedAt)
+				v.Grab.ImportedAt = &at
 			}
 		}
 		out.Items = append(out.Items, v)
@@ -425,3 +448,11 @@ func (h *handlers) writeProfileErr(w http.ResponseWriter, err error) {
 		writeErrWithLog(w, h.logger, "admin release profiles", apierror.Internal(err))
 	}
 }
+
+// deref is a nullable column's text, or "".
+func deref(s *string) string {
+	if s == nil {
+		return ""
+	}
+	return *s
+}