fix(downloads): humanized reasons and TechInfo on the download panel (DL-2b)

- board organize hint uses DEAI-2 reasonLine; add transfer_failed, blocked,
  blocked_by_conflict, main_failed, not_imported_kind, target_root_not_managed,
  download_removed to the reason table with tests
- download detail / plans tab: internal ids, raw codes and JSON moved into TechInfo
- library versions tech block switched to TechInfo (TODO(DEAI-2))
- copy: glossary terms (no 接管/候选), plan reason codes no longer shown raw

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

packages/contracts/src/reasons.ts

@@ -40,6 +40,14 @@ const REASONS: Record<string, ReasonText> = {
   timeout: { text: "操作超时", action: "稍后重试" },
   downloader_unavailable: { text: "下载器连不上", action: "在设置 → 下载器里测试连接" },
   downloader_error: { text: "下载器报错", action: "查看下载器日志" },
+  // DL-2b:下载面板整理状态、下载计划里出现的码
+  blocked: { text: "有冲突要先处理", action: "去待处理" },
+  blocked_by_conflict: { text: "有冲突，暂不整理" },
+  transfer_failed: { text: "文件没有整理成功", action: "在整理记录里查看失败的文件" },
+  main_failed: { text: "主文件整理失败，附属文件一起跳过" },
+  not_imported_kind: { text: "这类文件不入库" },
+  target_root_not_managed: { text: "目标目录不是本工具管理的媒体库目录", action: "在设置 → 媒体库与目录里检查" },
+  download_removed: { text: "下载任务已从下载器删除" },
 };
 
 /**