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>

web/src/lib/components/wanted/WantList.svelte

@@ -0,0 +1,263 @@
+<script lang="ts">
+  import { Album, ChevronDown, ListChecks, Search, X } from 'lucide-svelte';
+  import { useQueryClient } from '@tanstack/svelte-query';
+  import { createWantsQuery, removeWant, searchWant } from '#lib/api/wanted.js';
+  import { qk } from '#lib/api/queries.js';
+  import { errMessage } from '#lib/api/errors.js';
+  import { pushToast } from '#lib/stores/toast.svelte.js';
+  import { relativeTime } from '#lib/utils/relativeTime.js';
+  import ListContinuation from '#lib/components/ListContinuation.svelte';
+  import WantCandidates from '#lib/components/WantCandidates.svelte';
+  import type { SearchResult, Want, WantState } from '#lib/api/types.js';
+
+  // One tab of the Wanted view (M502 #5520–#5522): the albums still wanted,
+  // the missing albums wanted back, or the ones held. Each open want says
+  // what its last search found and how its download is getting on; Releases
+  // lists every candidate with its verdict, and Search runs one now.
+
+  let { state }: { state: WantState } = $props();
+
+  const client = useQueryClient();
+  const wantsStore = $derived(createWantsQuery(state));
+  const wants = $derived($wantsStore);
+  const items = $derived((wants.data?.pages ?? []).flatMap((p) => p.items) as Want[]);
+
+  let busy = $state<string | null>(null);
+  let searching = $state<string | null>(null);
+  let open = $state<string | null>(null);
+
+  async function onRemove(w: Want) {
+    busy = w.id;
+    try {
+      await removeWant(w.id);
+      pushToast(`${w.title} is off the wanted list.`);
+      await client.invalidateQueries({ queryKey: ['adminWants'] });
+    } catch (e) {
+      pushToast(errMessage(e), 'error');
+    } finally {
+      busy = null;
+    }
+  }
+
+  function searched(w: Want, r: SearchResult): string {
+    let said: string;
+    switch (r.outcome) {
+      case 'grabbed':
+        said = `Took ${r.grabbed ?? r.best_release}.`;
+        break;
+      case 'waiting':
+        said = `Found ${r.considered}; nothing taken. Releases shows why.`;
+        break;
+      case 'nothing':
+        said = r.considered ? `Found ${r.considered}, none of them ${w.title}.` : `Nothing found for ${w.title}.`;
+        break;
+      default:
+        said = r.error ?? 'The search failed.';
+    }
+    if (r.narrowed.length) said += ` ${r.narrowed.map((n) => n.label).join(', ')} didn't answer.`;
+    return said;
+  }
+
+  async function onSearch(w: Want) {
+    searching = w.id;
+    try {
+      const r = await searchWant(w.id);
+      pushToast(searched(w, r), r.outcome === 'error' ? 'error' : 'info');
+      await Promise.all([
+        client.invalidateQueries({ queryKey: ['adminWants'] }),
+        client.invalidateQueries({ queryKey: qk.wantCandidates(w.id) })
+      ]);
+    } catch (e) {
+      pushToast(errMessage(e), 'error');
+    } finally {
+      searching = null;
+    }
+  }
+
+  // A download still running, in a line: how far it has got, or what its
+  // import is doing or waiting on.
+  function downloading(w: Want): string | null {
+    const g = w.grab;
+    if (!g?.live) return null;
+    switch (g.import_state) {
+      case 'downloading':
+        return `Downloading ${Math.floor(g.progress * 100)}% · ${g.name}`;
+      case 'importing':
+        return `Downloaded; checking it is the album and filing it · ${g.name}`;
+      case 'waiting':
+        return `Downloaded; ${g.import_reason || 'waiting to be imported'}`;
+      case 'review':
+        return `Needs you: ${g.import_reason}`;
+      case 'failed':
+        return `Import failed: ${g.import_reason}`;
+    }
+    const who = g.origin === 'operator' ? 'taken by you' : 'taken by the schedule';
+    return `Downloading ${g.name}, ${who} ${relativeTime(g.grabbed_at)}`;
+  }
+
+  // What the schedule last did about a want, in a line.
+  function status(w: Want): string {
+    const live = downloading(w);
+    if (live) return live;
+    const s = w.search;
+    let said = 'Not searched yet';
+    if (s) {
+      const when = `Searched ${relativeTime(s.searched_at)}`;
+      switch (s.outcome) {
+        case 'nothing':
+          said = s.considered ? `${when}: ${s.considered} found, none of them this album` : `${when}: nothing found`;
+          break;
+        case 'waiting':
+          said = `${when}: ${s.considered} found, nothing taken`;
+          break;
+        case 'grabbed':
+          said = `${when}: took ${s.best_release}`;
+          break;
+        default:
+          said = `${when}: ${s.error}`;
+      }
+    }
+    if (w.grab?.import_state === 'refused') said += `. Last download refused: ${w.grab.import_reason}`;
+    return said;
+  }
+
+  // How a held album arrived, when Minstrel fetched it.
+  function arrived(w: Want): string | null {
+    const g = w.grab;
+    if (!g || g.import_state !== 'imported' || !g.imported_at) return null;
+    const n = g.imported_files === 1 ? '1 track' : `${g.imported_files} tracks`;
+    return `Imported ${n} ${relativeTime(g.imported_at)} from ${g.name}`;
+  }
+
+  const attention = (w: Want) => w.grab?.live && (w.grab.import_state === 'review' || w.grab.import_state === 'failed');
+
+  function why(w: Want): string {
+    if (w.reason === 'request') return w.requested_by ? `Requested by ${w.requested_by}` : 'Requested';
+    if (w.reason === 'follow') return 'New from a followed artist';
+    return 'Its files went missing';
+  }
+
+  function kind(w: Want): string {
+    const parts = [w.primary_type, ...w.secondary_types].filter(Boolean);
+    if (w.year) parts.push(w.year);
+    return parts.join(' · ');
+  }
+
+  function hideBroken(e: Event) {
+    (e.currentTarget as HTMLImageElement).style.display = 'none';
+  }
+</script>
+
+{#if wants.isPending}
+  <p class="text-text-secondary">Reading the wanted list…</p>
+{:else if wants.isError && !wants.isFetchNextPageError}
+  <p class="text-error-fg">Couldn't load the wanted list.</p>
+{:else if items.length === 0}
+  <div class="rounded-lg border border-border bg-surface p-6 text-center">
+    <ListChecks size={28} strokeWidth={1} class="mx-auto text-text-muted" />
+    <p class="mt-3 text-text-primary">
+      {#if state === 'held'}Nothing on the list has been held yet.
+      {:else if state === 'missing'}No missing albums are wanted back.
+      {:else}Nothing is wanted.{/if}
+    </p>
+    <p class="mt-1 text-sm text-text-secondary">
+      {#if state === 'missing'}
+        An album whose files stay missing past the grace window on the Missing files page lands here.
+      {:else}
+        A request you approve, a new release from a followed artist, or an album whose files went
+        missing lands here.
+      {/if}
+    </p>
+  </div>
+{:else}
+  <ul class="divide-y divide-border rounded-lg border border-border bg-surface">
+    {#each items as w (w.id)}
+      <li class="space-y-2 p-3" data-testid="want-row">
+        <div class="flex items-center gap-3">
+          <div class="relative flex h-14 w-14 shrink-0 items-center justify-center overflow-hidden rounded-md bg-surface-hover" aria-hidden="true">
+            <Album size={22} strokeWidth={1} class="text-text-muted" />
+            {#if w.image_url}
+              <img src={w.image_url} alt="" class="absolute inset-0 h-full w-full object-cover" loading="lazy" onerror={hideBroken} />
+            {/if}
+          </div>
+          <div class="min-w-0 flex-1 space-y-0.5">
+            <div class="truncate text-sm font-medium text-text-primary">
+              {#if w.album_id && w.held_at}
+                <a href="/albums/{w.album_id}" class="hover:underline">{w.title}</a>
+              {:else}
+                {w.title}
+              {/if}
+            </div>
+            <div class="truncate text-xs text-text-secondary">
+              {#if w.artist_id}
+                <a href="/artists/{w.artist_id}" class="hover:text-text-primary hover:underline">{w.artist_name}</a>
+              {:else}
+                {w.artist_name}
+              {/if}
+              {#if kind(w)}<span class="text-text-muted"> · {kind(w)}</span>{/if}
+            </div>
+            <div class="text-xs text-text-muted" data-testid="want-why">
+              {why(w)} · {w.held_at ? `held ${relativeTime(w.held_at)}` : `wanted ${relativeTime(w.wanted_at)}`}
+            </div>
+            {#if !w.held_at}
+              <div
+                class="text-xs {attention(w) ? 'text-text-primary' : 'truncate text-text-secondary'}"
+                data-testid="want-search"
+              >
+                {status(w)}
+                {#if attention(w)}
+                  <a href="/wanted/activity" class="ml-1 text-accent-fg hover:underline">Decide on Activity</a>
+                {/if}
+              </div>
+            {:else if arrived(w)}
+              <div class="truncate text-xs text-text-secondary" data-testid="want-arrived">{arrived(w)}</div>
+            {/if}
+          </div>
+          {#if !w.held_at}
+            <div class="flex shrink-0 flex-wrap justify-end gap-1.5">
+              <button
+                type="button"
+                onclick={() => onSearch(w)}
+                disabled={searching !== null || !!w.grab?.live}
+                aria-label="Search for {w.title} now"
+                class="inline-flex items-center gap-1 rounded-md border border-border px-2.5 py-1 text-xs text-text-secondary hover:bg-surface-hover hover:text-text-primary disabled:opacity-50"
+              >
+                <Search size={12} strokeWidth={2} /> {searching === w.id ? 'Searching…' : 'Search'}
+              </button>
+              <button
+                type="button"
+                onclick={() => (open = open === w.id ? null : w.id)}
+                aria-expanded={open === w.id}
+                aria-label="Releases found for {w.title}"
+                class="inline-flex items-center gap-1 rounded-md border border-border px-2.5 py-1 text-xs text-text-secondary hover:bg-surface-hover hover:text-text-primary"
+              >
+                Releases <ChevronDown size={12} strokeWidth={2} class={open === w.id ? 'rotate-180' : ''} />
+              </button>
+              <button
+                type="button"
+                onclick={() => onRemove(w)}
+                disabled={busy === w.id}
+                aria-label="Stop wanting {w.title}"
+                class="inline-flex items-center gap-1 rounded-md border border-border px-2.5 py-1 text-xs text-text-secondary hover:bg-surface-hover hover:text-text-primary disabled:opacity-50"
+              >
+                <X size={12} strokeWidth={2} /> Remove
+              </button>
+            </div>
+          {/if}
+        </div>
+        {#if open === w.id && !w.held_at}
+          <div class="sm:pl-[4.25rem]">
+            <WantCandidates wantId={w.id} title={w.title} />
+          </div>
+        {/if}
+      </li>
+    {/each}
+  </ul>
+
+  <ListContinuation
+    hasMore={!!wants.hasNextPage}
+    loading={wants.isFetchingNextPage}
+    failed={wants.isFetchNextPageError}
+    onMore={() => wants.fetchNextPage()}
+  />
+{/if}