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/web/app/components/downloads/download-detail.tsx

@@ -23,13 +23,11 @@ import { OrganizeWizard } from "~/components/organize-wizard/organize-wizard.tsx
 import { Button } from "~/components/ui/button.tsx";
 import { relTime } from "~/components/workbench/release-fields.ts";
 import { errorMessage } from "~/lib/api.ts";
-import { planReasonText } from "~/lib/labels.ts";
 import { humanizeReason, reasonCode, reasonLine } from "~/lib/reasons.ts";
 import { formatBytes, formatDateTime } from "~/lib/utils.ts";
 import { liveItems } from "./board-format.ts";
 import { BusinessTimeline } from "./business-timeline.tsx";
-
-const PLAN_PURPOSE_LABEL: Record<string, string> = { fill: "补缺", upgrade: "升级", replace_source: "换源" };
+import { WhySection } from "./plan-row.tsx";
 
 /** 进度:细线 + 文字;总量未知时不伪造百分比 */
 export function ProgressLine({ t }: { t: DownloadTask }) {
@@ -91,7 +89,7 @@ export function PauseResume({ t, size = "sm" }: { t: DownloadTask; size?: "sm" |
   );
 }
 
-/** 下载任务详情:状态、阈值说明、业务时间线、文件、关联计划 */
+/** 下载任务详情:状态、阈值说明、业务时间线、为什么下这个(DL-3)、文件 */
 export function DownloadDetail({ task, live }: { task: DownloadTask; live?: DownloadLive | null }) {
   const plan = usePlan(task.acquisitionPlanId);
   const names = useDownloaderNames();
@@ -157,6 +155,20 @@ export function DownloadDetail({ task, live }: { task: DownloadTask; live?: Down
         </p>
       ) : null}
 
+      {task.acquisitionPlanId ? (
+        <WhySection
+          planId={task.acquisitionPlanId}
+          extraTech={[
+            {
+              label: "计划状态",
+              value: plan.data
+                ? `${PLAN_STATUS_LABEL[plan.data.status]}${plan.data.statusReason ? ` · ${plan.data.statusReason}` : ""}`
+                : null,
+            },
+          ]}
+        />
+      ) : null}
+
       <DetailSection title="进度">
         <ProgressLine t={live ? { ...task, progress: live.progress } : task} />
         <KvList
@@ -194,28 +206,6 @@ export function DownloadDetail({ task, live }: { task: DownloadTask; live?: Down
         <BusinessTimeline events={trace.events} loading={trace.loading} />
       </DetailSection>
 
-      {plan.data ? (
-        <DetailSection title="下载计划">
-          <KvList
-            items={[
-              { label: "状态", value: PLAN_STATUS_LABEL[plan.data.status] },
-              { label: "用途", value: PLAN_PURPOSE_LABEL[plan.data.purpose] ?? plan.data.purpose },
-              { label: "预留空间", value: formatBytes(plan.data.reservedBytes, 1) },
-              { label: "说明", value: planReasonText(plan.data.statusReason), wide: true },
-            ]}
-          />
-          <TechInfo
-            className="mt-2"
-            items={[
-              { label: "计划 ID", value: plan.data.id, wide: true },
-              { label: "说明原码", value: plan.data.statusReason },
-            ]}
-          >
-            <JsonView label="评估依据" value={plan.data.evaluation} />
-          </TechInfo>
-        </DetailSection>
-      ) : null}
-
       {task.fileList?.length ? (
         <DetailSection title={`文件(${task.fileList.length})`}>
           <ul className="max-h-60 space-y-1 overflow-auto text-meta">