refactor(domain): introduce FeedRepository as the single KV access layer

Centralise the KV key schema and all get/put access behind a FeedRepository
class under src/domain/. Every feed/email/list/icon/websub/counter key was
previously inlined across ~12 modules with two divergent storeEmail and
addFeedToList implementations; the dead src/utils/storage.ts write path is
removed and the email key convention unified on feed:<id>:<ts>.

Behaviour-preserving: existing tests pass unchanged in logic, plus a new
feed-repository.test.ts covering CRUD, key builders, list ops and counters.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

src/domain/feed-repository.test.ts

@@ -0,0 +1,171 @@
+import { describe, it, expect } from "vitest";
+import { createMockEnv } from "../test/setup";
+import { FeedRepository } from "./feed-repository";
+import type {
+  Env,
+  FeedConfig,
+  FeedMetadata,
+  EmailData,
+  WebSubSubscription,
+} from "../types";
+
+const mockEnv = () => createMockEnv() as unknown as Env;
+
+const sampleConfig = (overrides: Partial<FeedConfig> = {}): FeedConfig => ({
+  title: "Test Feed",
+  language: "en",
+  created_at: 1000,
+  ...overrides,
+});
+
+const sampleEmail = (overrides: Partial<EmailData> = {}): EmailData => ({
+  subject: "Hello",
+  from: "news@example.com",
+  content: "<p>hi</p>",
+  receivedAt: 1234,
+  headers: {},
+  ...overrides,
+});
+
+describe("FeedRepository key schema", () => {
+  it("builds the canonical KV keys via the public API", () => {
+    const repo = new FeedRepository(mockEnv().EMAIL_STORAGE);
+    expect(repo.feedKeyPrefix("a.b.42")).toBe("feed:a.b.42:");
+    expect(repo.iconKey("example.com")).toBe("icon:example.com");
+    expect(repo.newEmailKey("a.b.42")).toMatch(/^feed:a\.b\.42:\d+$/);
+  });
+
+  it("recognises email keys vs config/metadata keys", () => {
+    const repo = new FeedRepository(mockEnv().EMAIL_STORAGE);
+    expect(repo.isEmailKey("a.b.42", "feed:a.b.42:config")).toBe(false);
+    expect(repo.isEmailKey("a.b.42", "feed:a.b.42:metadata")).toBe(false);
+    expect(repo.isEmailKey("a.b.42", "feed:a.b.42:1700000000000")).toBe(true);
+  });
+
+  it("recovers the feed id from an email key", () => {
+    const repo = new FeedRepository(mockEnv().EMAIL_STORAGE);
+    expect(repo.feedIdFromEmailKey("feed:a.b.42:1700000000000")).toBe("a.b.42");
+  });
+});
+
+describe("FeedRepository config & metadata", () => {
+  it("round-trips and deletes a feed config", async () => {
+    const repo = new FeedRepository(mockEnv().EMAIL_STORAGE);
+    expect(await repo.getConfig("a.b.42")).toBeNull();
+    await repo.putConfig("a.b.42", sampleConfig());
+    expect(await repo.getConfig("a.b.42")).toMatchObject({
+      title: "Test Feed",
+    });
+    await repo.deleteConfig("a.b.42");
+    expect(await repo.getConfig("a.b.42")).toBeNull();
+  });
+
+  it("round-trips and deletes feed metadata", async () => {
+    const repo = new FeedRepository(mockEnv().EMAIL_STORAGE);
+    const meta: FeedMetadata = { emails: [] };
+    await repo.putMetadata("a.b.42", meta);
+    expect(await repo.getMetadata("a.b.42")).toEqual(meta);
+    await repo.deleteMetadata("a.b.42");
+    expect(await repo.getMetadata("a.b.42")).toBeNull();
+  });
+});
+
+describe("FeedRepository emails", () => {
+  it("stores and reads an email under a minted key", async () => {
+    const repo = new FeedRepository(mockEnv().EMAIL_STORAGE);
+    const key = repo.newEmailKey("a.b.42");
+    await repo.putEmail(key, sampleEmail());
+    expect(await repo.getEmail(key)).toMatchObject({ subject: "Hello" });
+    await repo.deleteEmail(key);
+    expect(await repo.getEmail(key)).toBeNull();
+  });
+
+  it("lists every key under a feed prefix", async () => {
+    const repo = new FeedRepository(mockEnv().EMAIL_STORAGE);
+    await repo.putConfig("a.b.42", sampleConfig());
+    await repo.putMetadata("a.b.42", { emails: [] });
+    const emailKey = repo.newEmailKey("a.b.42");
+    await repo.putEmail(emailKey, sampleEmail());
+
+    const listed = await repo.listFeedKeys("a.b.42");
+    expect(listed.names).toContain("feed:a.b.42:config");
+    expect(listed.names).toContain("feed:a.b.42:metadata");
+    expect(listed.names).toContain(emailKey);
+    expect(listed.names.filter((k) => repo.isEmailKey("a.b.42", k))).toEqual([
+      emailKey,
+    ]);
+  });
+});
+
+describe("FeedRepository feed list", () => {
+  it("adds, updates, lists and removes feeds with expiry", async () => {
+    const repo = new FeedRepository(mockEnv().EMAIL_STORAGE);
+    await repo.addToList("a.b.42", "One", "desc", 5000);
+    await repo.addToList("c.d.99", "Two");
+
+    let feeds = await repo.listFeeds();
+    expect(feeds).toHaveLength(2);
+    expect(feeds.find((f) => f.id === "a.b.42")).toMatchObject({
+      title: "One",
+      expires_at: 5000,
+    });
+
+    await repo.updateInList("a.b.42", "One-updated", undefined, undefined);
+    feeds = await repo.listFeeds();
+    const updated = feeds.find((f) => f.id === "a.b.42");
+    expect(updated).toMatchObject({ title: "One-updated" });
+    expect(updated?.expires_at).toBeUndefined();
+
+    expect(await repo.removeFromList("a.b.42")).toBe(true);
+    expect(await repo.removeFromList("missing")).toBe(false);
+    feeds = await repo.listFeeds();
+    expect(feeds.map((f) => f.id)).toEqual(["c.d.99"]);
+  });
+
+  it("bulk-removes only the matching ids", async () => {
+    const repo = new FeedRepository(mockEnv().EMAIL_STORAGE);
+    await repo.addToList("a.b.42", "One");
+    await repo.addToList("c.d.99", "Two");
+    await repo.addToList("e.f.10", "Three");
+
+    const removed = await repo.removeFromListBulk(["a.b.42", "e.f.10", "nope"]);
+    expect(removed.sort()).toEqual(["a.b.42", "e.f.10"]);
+    expect((await repo.listFeeds()).map((f) => f.id)).toEqual(["c.d.99"]);
+  });
+});
+
+describe("FeedRepository counters, icons, websub", () => {
+  it("round-trips raw counters", async () => {
+    const repo = new FeedRepository(mockEnv().EMAIL_STORAGE);
+    expect(await repo.getCountersRaw()).toBeNull();
+    await repo.putCounters({
+      feeds_created: 1,
+      feeds_deleted: 0,
+      emails_received: 2,
+      emails_rejected: 0,
+      unsubscribes_sent: 0,
+    });
+    expect(await repo.getCountersRaw()).toMatchObject({ emails_received: 2 });
+  });
+
+  it("stores and reads favicons as text or json", async () => {
+    const repo = new FeedRepository(mockEnv().EMAIL_STORAGE);
+    expect(await repo.getIconText("example.com")).toBeNull();
+    await repo.putIcon("example.com", JSON.stringify({ data: null }), 60);
+    expect(await repo.getIconText("example.com")).toBe('{"data":null}');
+    expect(await repo.getIconJson<{ data: null }>("example.com")).toEqual({
+      data: null,
+    });
+  });
+
+  it("round-trips websub subscriptions and counts them", async () => {
+    const repo = new FeedRepository(mockEnv().EMAIL_STORAGE);
+    expect(await repo.getSubscriptions("a.b.42")).toEqual([]);
+    const subs: WebSubSubscription[] = [
+      { callbackUrl: "https://r.example/cb", expiresAt: 9999 },
+    ];
+    await repo.saveSubscriptions("a.b.42", subs);
+    expect(await repo.getSubscriptions("a.b.42")).toEqual(subs);
+    expect(await repo.countSubscriptionKeys()).toBe(1);
+  });
+});