pipeline: equal-width columns + per-column clear/stop button

Extract a ColumnShell component so all four columns share the same flex-1
basis-0 width (no more 24/16/18/16 rem mix) and the same header layout
(title + count + optional action button on the right).

Per-column actions:
- Review:     'Skip all' → POST /api/review/skip-all (new endpoint, sets all
              pending non-noop plans to skipped in one update)
- Queued:     'Clear'    → POST /api/execute/clear (existing; cancels pending jobs)
- Processing: 'Stop'     → POST /api/execute/stop (new; SIGTERMs the running
              ffmpeg via a tracked Bun.spawn handle, runJob's catch path
              marks the job error and cleans up)
- Done:       'Clear'    → POST /api/execute/clear-completed (existing)

All destructive actions confirm before firing.

src/features/pipeline/ReviewColumn.tsx

@@ -1,4 +1,5 @@
 import { api } from "~/shared/lib/api";
+import { ColumnShell } from "./ColumnShell";
 import { PipelineCard } from "./PipelineCard";
 import { SeriesCard } from "./SeriesCard";
 
@@ -11,6 +12,12 @@ interface ReviewColumnProps {
 
 export function ReviewColumn({ items, total, jellyfinUrl, onMutate }: ReviewColumnProps) {
 	const truncated = total > items.length;
+
+	const skipAll = async () => {
+		if (!confirm(`Skip all ${total} pending items? They won't be processed unless you unskip them.`)) return;
+		await api.post("/api/review/skip-all");
+		onMutate();
+	};
 	// Group by series (movies are standalone)
 	const movies = items.filter((i: any) => i.type === "Movie");
 	const seriesMap = new Map<string, { name: string; key: string; jellyfinId: string | null; episodes: any[] }>();
@@ -45,11 +52,12 @@ export function ReviewColumn({ items, total, jellyfinUrl, onMutate }: ReviewColu
 	};
 
 	return (
-		<div className="flex flex-col w-96 min-w-96 min-h-0 bg-gray-50 rounded-lg">
-			<div className="px-3 py-2 border-b font-medium text-sm">
-				Review <span className="text-gray-400">({truncated ? `${items.length} of ${total}` : total})</span>
-			</div>
-			<div className="flex-1 overflow-y-auto p-2 space-y-2">
+		<ColumnShell
+			title="Review"
+			count={truncated ? `${items.length} of ${total}` : total}
+			action={total > 0 ? { label: "Skip all", onClick: skipAll } : undefined}
+		>
+			<div className="space-y-2">
 				{allItems.map((entry) => {
 					if (entry.type === "movie") {
 						return (
@@ -86,6 +94,6 @@ export function ReviewColumn({ items, total, jellyfinUrl, onMutate }: ReviewColu
 					</p>
 				)}
 			</div>
-		</div>
+		</ColumnShell>
 	);
 }