feat(downloads): restore package disclosure motion and remaining size

Restore smooth 300 ms expand and collapse transitions without removing row virtualization. Limit animated disclosure rows globally, preserve live item updates during motion, support rapid reversal, and keep large queues bounded.

Add a Remaining sidebar metric that sums only unfinished known bytes while clearly marking unknown open sizes. Cover multi-package limits, live transition merges, honest remaining-size semantics, translations, and accessibility.

src/renderer/views/downloads/DownloadsView.tsx

@@ -19,6 +19,8 @@ export interface DownloadsStatusModel {
   sessionBytes: number;
   total: string;
   totalBytes: number;
+  remaining: string;
+  remainingBytes: number;
   hosters: number;
   speed: string;
   eta: string;
@@ -43,9 +45,10 @@ export interface DownloadsViewModel extends DownloadsViewModelCore {
   editingName: string;
   columnOrder: readonly string[];
   gridTemplate: string;
-  sortColumn?: DownloadSortColumn;
-  sortDirection?: "asc" | "desc";
-  status: DownloadsStatusModel;
+  sortColumn?: DownloadSortColumn;
+  sortDirection?: "asc" | "desc";
+  disclosureRevision: number;
+  status: DownloadsStatusModel;
 }
 
 export interface DownloadsViewActions extends DownloadsTableActions {
@@ -106,6 +109,7 @@ export function DownloadsSidebarStatus({ model }: { model: DownloadsViewModel })
     { label: "Links", metric: "links", numericValue: model.status.links, value: integerFormatter.format(model.status.links) },
     { label: "Sitzung", metric: "session", numericValue: model.status.sessionBytes, value: model.status.session },
     { label: "Gesamt", metric: "total", numericValue: model.status.totalBytes, value: model.status.total },
+    { label: "Verbleibend", metric: "remaining", numericValue: model.status.remainingBytes, value: model.status.remaining },
     { label: "Hoster", metric: "hosters", numericValue: model.status.hosters, value: integerFormatter.format(model.status.hosters) }
   ];
   return <section className="downloads-sidebar-status" data-visual-region="downloads-sidebar-status" aria-label="Downloadstatus">{entries.map((entry) => <div key={entry.metric}><span>{entry.label}</span><RollingMetricValue numericValue={entry.numericValue} value={entry.value} /></div>)}<div><span>Geschwindigkeit</span><strong data-status-metric="speed">{speed}</strong></div><div><span>ETA</span><strong data-status-metric="eta">{eta}</strong></div></section>;