feat(web): 前端插槽设施，作品页与整理记录行挂「补字幕」

- lib/slots.ts 按位置注册(侧栏入口、作品页操作区 / 面板区、整理记录行操作、设置分区),默认直接显示;
  components/slots 挂载点:面板类直接渲染,动作类渲染成按钮 / 菜单项、对话框在菜单外渲染
- 作品页操作区与面板区、整理记录行菜单接入插槽;补字幕改由 features/subtitles.tsx 注册,
  作品页按钮行为不变,整理记录行菜单新增「补字幕」(成功 / 部分成功的入库类整理)

Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01Cxwgnn2pbzQ7rXv3rq7fei

apps/web/app/features/index.ts

@@ -0,0 +1,5 @@
+// 功能模块的前端插槽注册汇总(ADR-006)。新增功能:在本目录加 <功能>.tsx 导出 register(registry),在这里调用一次。
+import { slots } from "~/lib/slots.ts";
+import { registerSubtitles } from "./subtitles.tsx";
+
+registerSubtitles(slots);

apps/web/app/features/subtitles.tsx

@@ -0,0 +1,37 @@
+import { Captions } from "lucide-react";
+import { SubtitleDialog } from "~/components/subtitles/subtitle-dialog.tsx";
+import type { SlotRegistry } from "~/lib/slots.ts";
+
+// 补字幕(功能模块样板,ADR-006):作品页操作区「补字幕」、整理记录行菜单「补字幕」,都打开同一个补字幕对话框。
+
+export function registerSubtitles(registry: SlotRegistry): void {
+  registry.register("entity.actions", {
+    id: "subtitles.entity",
+    feature: "subtitles",
+    label: "补字幕",
+    icon: Captions,
+    visible: ({ entity }) => entity.status !== "merged",
+    Dialog: ({ entity, onClose }) => (
+      <SubtitleDialog entityId={entity.id} title={entity.title} open onOpenChange={(o) => !o && onClose()} />
+    ),
+  });
+  registry.register("organize.record.actions", {
+    id: "subtitles.record",
+    feature: "subtitles",
+    label: "补字幕",
+    icon: Captions,
+    // 入库成功(或部分成功)且认到作品的整理才有视频可配字幕
+    visible: ({ record }) =>
+      !!record.media &&
+      (record.status === "succeeded" || record.status === "partial") &&
+      ["copy", "move", "in_place"].includes(record.action),
+    Dialog: ({ record, onClose }) => (
+      <SubtitleDialog
+        entityId={record.media!.entityId}
+        title={record.media!.title}
+        open
+        onOpenChange={(o) => !o && onClose()}
+      />
+    ),
+  });
+}