feat: a held album below the quality you settle for, or holding a video rip, stays wanted for a better copy, and the import replaces the old tracks with their likes and plays carried over (M502 #5524)

- acquisition_settings.upgrade_until (default High quality lossy, Lidarr's
  cutoff, note #5527; "" is off), an "Upgrade until" row under Searching.
- The wanted worker judges held albums hourly: tier per format from size per
  second (the scanner records no bitrate), the album's worst. Below the
  cutoff it is wanted for quality; a video rip among its tracks always.
- The schedule searches upgrades weekly, after open wants; a release no
  better than the copy held is refused ("not_better").
- The import matches each file to the track it would replace (recording,
  then disc/track) and replaces it when it is a rip or the file is a better
  tier: over the same path in one rename, or filed beside it and the old
  track folded in (library.ReplaceTrack: file first, then foldTrackInto).
  Nothing better: the release is set aside.
- Collection › Upgrades (Lidarr's Cutoff Unmet); Suspect sources says when a
  clean copy was looked for instead of Lidarr's search.

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

internal/release/release_test.go

@@ -251,3 +251,61 @@ func TestParseTorrent_FilesAndInfohash(t *testing.T) {
 		t.Error("HTML parsed as a torrent")
 	}
 }
+
+func TestTierOfFile(t *testing.T) {
+	cases := []struct {
+		format string
+		kbps   int
+		want   Tier
+		ok     bool
+	}{
+		{"flac", 900, TierLossless, true},
+		{"FLAC", 2800, TierLosslessHiRes, true},
+		{"m4a", 750, TierLossless, true},
+		{"m4a", 256, TierLossyHigh, true},
+		{"mp3", 320, TierLossyHigh, true},
+		{"mp3", 245, TierLossyHigh, true}, // a V0, by size
+		{"mp3", 192, TierLossyLow, true},
+		{"mp3", 128, TierLossyPoor, true},
+		{"mp3", 96, TierLossyTrash, true},
+		{"opus", 160, TierLossyLow, true},
+		{"wma", 192, TierUnknown, false},
+		{"mp3", 0, TierLossyStandard, false},
+	}
+	for _, c := range cases {
+		got, ok := TierOfFile(c.format, c.kbps)
+		if got != c.want || ok != c.ok {
+			t.Errorf("TierOfFile(%q, %d) = %s, %v; want %s, %v", c.format, c.kbps, got, ok, c.want, c.ok)
+		}
+	}
+}
+
+func TestFileKbpsAndWords(t *testing.T) {
+	// 5 MB over 3:30 of audio is about 190 kbps.
+	k := FileKbps(5_000_000, 210_000)
+	if k != 190 {
+		t.Fatalf("FileKbps = %d, want 190", k)
+	}
+	if got := HeldWords("mp3", TierLossyLow, 191); got != "MP3, about 192 kbps" {
+		t.Errorf("HeldWords = %q", got)
+	}
+	if got := HeldWords("flac", TierLossless, 900); got != "FLAC" {
+		t.Errorf("HeldWords = %q", got)
+	}
+	if FileKbps(0, 1000) != 0 || FileKbps(1000, 0) != 0 {
+		t.Error("FileKbps with nothing to measure is 0")
+	}
+}
+
+func TestHeldCopy_TakesTheWorstFormat(t *testing.T) {
+	h, ok := HeldCopy([]HeldFormat{
+		{Format: "flac", Bytes: 300_000_000, Ms: 2_400_000},
+		{Format: "mp3", Bytes: 4_800_000, Ms: 200_000}, // 192 kbps
+	})
+	if !ok || h.Tier != TierLossyLow || h.Words != "MP3, about 192 kbps" {
+		t.Fatalf("HeldCopy = %+v, %v", h, ok)
+	}
+	if _, ok := HeldCopy([]HeldFormat{{Format: "wma", Bytes: 1, Ms: 1}}); ok {
+		t.Error("a format the ladder can't place says nothing")
+	}
+}