feat(downloads): fold download plans into download panel (DL-3)

- Waiting plans (approval / disk space / automation off / queued) are
  active-segment rows on /download-tasks/board, merged by created_at,
  counted, with approve / cancel actions; ?plan= deep links and legacy
  /downloads/plans routes redirect to the panel
- Download detail shows "why this download" (source, purpose, replaced
  version, reasons); raw evaluation in tech info
- Failed / cancelled / expired plans appear in the entity download
  history; rejected / revoked / expired approvals close draft plans
- New GET /acquisition-plans/{id}/why, POST /acquisition-plans/{id}/cancel
- User-facing copy no longer says 下载计划; glossary updated

Co-Authored-By: Claude Opus 5.5 <[email protected]>

apps/server/src/modules/mcp/catalog.ts

@@ -144,7 +144,7 @@ export const MCP_PROMPTS: readonly McpPromptDef[] = [
   {
     name: "acquire_title",
     title: "收录一部作品",
-    description: "从查作品到生成下载计划；提交下载要有授权。",
+    description: "从查作品到准备下载；提交下载要有授权。",
     arguments: [
       { name: "title", description: "作品标题", required: true },
       { name: "year", description: "年份（可选）", required: false },
@@ -154,8 +154,8 @@ export const MCP_PROMPTS: readonly McpPromptDef[] = [
         `目标：收录「${a.title ?? ""}」${a.year ? `（${a.year}）` : ""}。`,
         "1. catalog__lookup 确认作品，拿不准时列出候选，不要猜；",
         "2. release__search 找资源，release__inspect 看细节；",
-        "3. download__plan 生成下载计划并说明选择理由；",
-        "4. 有持续授权时再调用 download__submit；返回 unauthorized 就停下，给出计划 ID 等审批。",
+        "3. download__plan 准备下载（返回 planId）并说明选择理由；",
+        "4. 有持续授权时再调用 download__submit；返回 unauthorized 就停下，给出 planId 等审批。",
       ].join("\n"),
   },
   {