feat(adapters): RSS and PT site adapters ported from MoviePilot v3 + mocks (W1-3b)

- rss: port of MP RssHelper._parse_impl/get_rss_link semantics with safe
  XML (entities off, DTD/ENTITY rejected, size/item caps), ETag/Last-Modified,
  backoff + Retry-After, circuit breaker with manual reset, passkey redaction,
  overlap-window GUID+digest dedupe
- sites/spider: TS port of MP SiteSpider (indexer schema, search URL builder,
  field DSL, filters, Jinja templates via nunjucks, login-page detection);
  audiences definition hand-written as JSON; raw category id preserved;
  shared per-site token bucket
- sites/mteam: port of MP MTorrentSpider (params, result mapping, promo
  factors, genDlToken flow) without embedding the API key in enclosures;
  business code/message checks
- testkit: mock RSS server, mock NexusPHP site, mock M-Team API
- docs: W1-3b migration mapping appended to porting ledger

Co-Authored-By: Claude Fable 5.1 <[email protected]>

packages/adapters/src/sites/definitions/index.ts

@@ -0,0 +1,16 @@
+import type { IndexerDefinition } from "../spider/schema";
+import audiencesJson from "./audiences.json";
+
+/** 站点定义最小校验(随产品发布的定义文件;加站只需新增 JSON 并在此登记)。 */
+export function loadIndexerDefinition(json: unknown): IndexerDefinition {
+  const d = json as Partial<IndexerDefinition>;
+  if (!d || typeof d !== "object") throw new Error("站点定义必须是对象");
+  for (const k of ["id", "name", "domain"] as const) {
+    if (typeof d[k] !== "string" || !d[k]) throw new Error(`站点定义缺少 ${k}`);
+  }
+  if (!d.torrents?.list?.selector || !d.torrents.fields) throw new Error(`站点定义 ${d.id} 缺少 torrents.list/fields`);
+  if (!d.umt?.version || !d.umt.timezone || !d.umt.rateLimit) throw new Error(`站点定义 ${d.id} 缺少 umt 扩展`);
+  return d as IndexerDefinition;
+}
+
+export const audiencesDefinition: IndexerDefinition = loadIndexerDefinition(audiencesJson);