feat(anime): add anime browser powered by Aniyomi extensions

- Add `subminer anime` / `--anime` and a tray entry to open a browser that searches installed Aniyomi extension sources, shows cover art and episodes, and plays into mpv with overlay/mining attached
- Add an Extensions tab to add repos and install/update/remove sources, and per-source settings for sources needing config
- Support searching all sources at once with streaming, per-source results and status
- Prefer Japanese audio/subtitle tracks from the source and keep the primary subtitle slot reserved for Japanese
- Fix window/tray/Dock handling so the browser and mpv can be switched between without quitting the app or losing the Dock icon
- Add anime.repos, anime.extensionsDir, anime.preferredQuality config keys (no bundled repos or discovery)

src/anime-bridge/multi-source-search.ts

@@ -0,0 +1,85 @@
+import type { SourceSearchFailure } from '../types/anime-browser';
+
+/**
+ * Running one query against every installed source at once.
+ *
+ * Each source is a separate extension behind the same single-threaded bridge,
+ * so the fan-out is bounded rather than unleashed: a dozen extensions all
+ * uploading and searching at once starves the ones the user is waiting on.
+ */
+
+/** Enough to hide the latency of a slow source without queueing the bridge. */
+const DEFAULT_CONCURRENCY = 4;
+
+export interface SourceTarget {
+  id: string;
+  name: string;
+}
+
+export interface FanOutResult<T> {
+  /** One entry per source that succeeded, in source order. */
+  results: T[];
+  /** One entry per source that threw, in source order. */
+  failures: SourceSearchFailure[];
+}
+
+/**
+ * Run `task` against every source, at most `concurrency` at a time.
+ *
+ * A source that throws becomes a failure instead of rejecting the whole call —
+ * one misconfigured extension must not hide every other source's results.
+ */
+export async function mapSourcesConcurrently<S extends SourceTarget, T>(
+  sources: S[],
+  task: (source: S) => Promise<T>,
+  concurrency: number = DEFAULT_CONCURRENCY,
+): Promise<FanOutResult<T>> {
+  // Slots keep the output in source order regardless of completion order, so
+  // the same query lays out the same way twice.
+  const results: Array<{ value: T } | null> = sources.map(() => null);
+  const failures: Array<SourceSearchFailure | null> = sources.map(() => null);
+  let next = 0;
+
+  const worker = async (): Promise<void> => {
+    for (;;) {
+      const index = next;
+      next += 1;
+      const source = sources[index];
+      if (!source) return;
+      try {
+        results[index] = { value: await task(source) };
+      } catch (error) {
+        failures[index] = {
+          sourceId: source.id,
+          sourceName: source.name,
+          error: error instanceof Error ? error.message : String(error),
+        };
+      }
+    }
+  };
+
+  const workers = Math.max(1, Math.min(concurrency, sources.length));
+  await Promise.all(Array.from({ length: workers }, () => worker()));
+
+  return {
+    results: results
+      .filter((slot): slot is { value: T } => slot !== null)
+      .map((slot) => slot.value),
+    failures: failures.filter((slot): slot is SourceSearchFailure => slot !== null),
+  };
+}
+
+/**
+ * Round-robin merge, so the grid opens with one hit from each source rather
+ * than the whole of the first source before the second one starts.
+ */
+export function interleave<T>(groups: T[][]): T[] {
+  const merged: T[] = [];
+  const longest = groups.reduce((max, group) => Math.max(max, group.length), 0);
+  for (let index = 0; index < longest; index += 1) {
+    for (const group of groups) {
+      if (index < group.length) merged.push(group[index] as T);
+    }
+  }
+  return merged;
+}