feat(download): 下载器可设「H&R 未知也可清理」（M2）

下载器策略加 hnrUnknownCleanable(缺省关,保持现状):保种天数到期、站点 H&R 要求未知
(M-Team、接管任务、站点没配 H&R)的任务视为可清理;H&R 明确未满足的不受影响。
空间不足事项里写明有多少任务因 H&R 未知没清理、可在哪里放行。

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

apps/web/app/components/settings/instances.tsx

@@ -97,16 +97,20 @@ const POLICY_FIELDS = [
   ["targetPct", "cleanupTargetPercent"],
   ["seedDays", "seedRetentionDays"],
 ] as const;
-function policyForm(r: DownloaderInstance): Record<string, string> {
+function policyForm(r: DownloaderInstance): Record<string, string | boolean> {
   const p = ((r.settings as { policy?: Record<string, unknown> }).policy ?? {}) as Record<string, unknown>;
-  return Object.fromEntries(POLICY_FIELDS.map(([f, k]) => [f, typeof p[k] === "number" ? String(p[k]) : ""]));
+  return {
+    ...Object.fromEntries(POLICY_FIELDS.map(([f, k]) => [f, typeof p[k] === "number" ? String(p[k]) : ""])),
+    hnrUnknownCleanable: p.hnrUnknownCleanable === true,
+  };
 }
-function policyBody(v: FormValues): Record<string, number> {
-  const out: Record<string, number> = {};
+function policyBody(v: FormValues): Record<string, number | boolean> {
+  const out: Record<string, number | boolean> = {};
   for (const [f, k] of POLICY_FIELDS) {
     const raw = String(v[f] ?? "").trim();
     if (raw !== "" && Number.isFinite(Number(raw))) out[k] = Number(raw);
   }
+  if (v.hnrUnknownCleanable === true) out.hnrUnknownCleanable = true;
   return out;
 }
 
@@ -202,6 +206,12 @@ function DownloadersTable() {
             placeholder: "留空用全局",
             hint: "入库后至少保留几天再允许清理；公网 BT 可填 0（站点 H&R 要求仍然遵守）",
           },
+          {
+            name: "hnrUnknownCleanable",
+            label: "H&R 未知也可清理",
+            kind: "switch",
+            hint: "保种天数到期后，没给出 H&R 要求的任务（如 M-Team、接管的任务、站点没配 H&R）也允许清理；默认不清理",
+          },
           {
             name: "isDefault",
             label: "设为默认下载器",
@@ -223,6 +233,7 @@ function DownloadersTable() {
           resumePct: "",
           targetPct: "",
           seedDays: "",
+          hnrUnknownCleanable: false,
           isDefault: false,
           enabled: true,
         },