refactor: separate Feed domain state from persistence DTO

Move four DDD tensions on the Feed aggregate to ground:

- #1 The aggregate now holds a domain FeedState (camelCase) instead of the
  snake_case FeedConfig DTO; infrastructure/feed-mapper.ts owns the
  FeedState<->FeedConfig/FeedListItem translation as the sole snake_case site
  outside the HTTP edge.
- #3 Replace the edit() recomputeExpiry control flag with a Lifetime VO:
  passing a lifetime recomputes expiry, omitting it preserves the current one
  (the dashboard quick-edit path).
- #4 Domain events carry their own feedId; dispatchFeedEvents centralizes the
  drain+dispatch in the application layer (no more manual pullEvents at call
  sites), keeping infra->application dependency direction intact.
- #6 Rename FeedId.fromTrusted to FeedId.unchecked to make the absence of
  revalidation explicit.

Adds Lifetime + feed-mapper round-trip tests. 353 tests green, tsc clean,
wrangler dry-run OK. Docs (CLAUDE.md) synced.

Co-Authored-By: Claude Opus 4.7 <[email protected]>

src/infrastructure/feed-mapper.test.ts

@@ -0,0 +1,45 @@
+import { describe, it, expect } from "vitest";
+import { fromConfigDTO, toConfigDTO, toListItemDTO } from "./feed-mapper";
+import { FeedId } from "../domain/value-objects/feed-id";
+import type { FeedConfig } from "../types";
+
+const fullConfig: FeedConfig = {
+  title: "News",
+  description: "desc",
+  language: "en",
+  author: "Jane",
+  allowed_senders: ["[email protected]"],
+  blocked_senders: ["[email protected]"],
+  created_at: 1000,
+  updated_at: 2000,
+  expires_at: 3000,
+};
+
+describe("feed-mapper", () => {
+  it("round-trips a full config DTO through domain state unchanged", () => {
+    expect(toConfigDTO(fromConfigDTO(fullConfig))).toEqual(fullConfig);
+  });
+
+  it("defaults absent sender lists to empty arrays on the domain side", () => {
+    const state = fromConfigDTO({
+      title: "T",
+      language: "en",
+      created_at: 1,
+    });
+    expect(state.allowedSenders).toEqual([]);
+    expect(state.blockedSenders).toEqual([]);
+  });
+
+  it("projects the feeds:list item from domain state", () => {
+    const item = toListItemDTO(
+      FeedId.unchecked("a.b.42"),
+      fromConfigDTO(fullConfig),
+    );
+    expect(item).toEqual({
+      id: "a.b.42",
+      title: "News",
+      description: "desc",
+      expires_at: 3000,
+    });
+  });
+});