refactor: invert application↔routes boundary (Track B — points 3, 6a)

- Point 3: move the feed/email storage-cleanup helpers (purgeFeedKeysStep,
  collectUnsubscribeUrls, purgeExpiredFeeds, deleteKeysWithConcurrency,
  deleteAttachmentsForEmails) out of routes/admin/helpers.ts into
  src/application/feed-cleanup.ts, so the application layer no longer imports
  from routes/. deleteFeedRecord no longer takes a Hono Context: it accepts a
  BackgroundScheduler ((task) => void) and the HTTP edge passes
  (p) => waitUntilSafe(c, p). Application/domain are now Hono-Context-free.
- Point 6a: rename the misleadingly-named Feed.rename → Feed.editDetails (it
  edits title + description), and feed-service.renameFeed → editFeedDetails.

CLAUDE.md source layout updated. 351 tests pass; tsc --noEmit clean.

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

src/routes/admin/emails.tsx

@@ -5,7 +5,7 @@ import { Layout, clampText } from "./ui";
 import {
   deleteAttachmentsForEmails,
   deleteKeysWithConcurrency,
-} from "./helpers";
+} from "../../application/feed-cleanup";
 import { FeedRepository } from "../../infrastructure/feed-repository";
 import { FeedId } from "../../domain/value-objects/feed-id";
 import {

src/routes/admin/feeds.tsx

@@ -8,7 +8,10 @@ import { logger } from "../../infrastructure/logger";
 import { sendUnsubscribes } from "../../infrastructure/unsubscribe";
 import { getAttachmentBucket } from "../../infrastructure/attachments";
 import { Layout } from "./ui";
-import { purgeFeedKeysStep, collectUnsubscribeUrls } from "./helpers";
+import {
+  purgeFeedKeysStep,
+  collectUnsubscribeUrls,
+} from "../../application/feed-cleanup";
 import { FeedRepository } from "../../infrastructure/feed-repository";
 import { FeedId } from "../../domain/value-objects/feed-id";
 import {
@@ -419,7 +422,7 @@ feedsRouter.post("/:feedId/delete", async (c) => {
   const wantsJson = (c.req.header("Accept") || "").includes("application/json");
 
   try {
-    await deleteFeedRecord(c, env, feedId);
+    await deleteFeedRecord(env, feedId, (p) => waitUntilSafe(c, p));
 
     if (wantsJson) {
       return c.json({ ok: true, feedId });

src/routes/admin/helpers.ts

@@ -1,143 +0,0 @@
-import { EmailData, EmailMetadata, Env } from "../../types";
-import { logger } from "../../infrastructure/logger";
-import { getAttachmentBucket } from "../../infrastructure/attachments";
-import { FeedRepository } from "../../infrastructure/feed-repository";
-import { FeedId } from "../../domain/value-objects/feed-id";
-
-// Delete the R2 attachments belonging to the given email keys. Call before the
-// emails are removed from feed metadata, while `emails` still carries their
-// attachmentIds.
-export async function deleteAttachmentsForEmails(
-  env: Env,
-  emails: EmailMetadata[],
-  keys: Iterable<string>,
-): Promise<void> {
-  const keySet = new Set(keys);
-  const attachmentIds = emails
-    .filter((e) => keySet.has(e.key))
-    .flatMap((e) => e.attachmentIds ?? []);
-  if (attachmentIds.length === 0) return;
-
-  const bucket = getAttachmentBucket(env);
-  if (!bucket) return;
-
-  await Promise.allSettled(attachmentIds.map((id) => bucket.delete(id)));
-}
-
-export async function deleteKeysWithConcurrency(
-  emailStorage: KVNamespace,
-  keys: string[],
-  concurrency: number,
-): Promise<{ ok: string[]; failed: string[] }> {
-  const uniqueKeys = Array.from(new Set(keys.filter(Boolean)));
-  const ok: string[] = [];
-  const failed: string[] = [];
-  const limit = Math.max(1, Math.floor(concurrency) || 1);
-
-  for (let i = 0; i < uniqueKeys.length; i += limit) {
-    const batch = uniqueKeys.slice(i, i + limit);
-    const results = await Promise.allSettled(
-      batch.map((key) => emailStorage.delete(key)),
-    );
-    results.forEach((result, idx) => {
-      const key = batch[idx];
-      if (result.status === "fulfilled") {
-        ok.push(key);
-      } else {
-        failed.push(key);
-      }
-    });
-  }
-
-  return { ok, failed };
-}
-
-/**
- * Read a feed's stored RFC 8058 one-click unsubscribe URLs (one per sender).
- * Must be called before the feed metadata is deleted. Never throws.
- */
-export async function collectUnsubscribeUrls(
-  emailStorage: KVNamespace,
-  feedId: string,
-): Promise<string[]> {
-  try {
-    const metadata = await new FeedRepository(emailStorage).getMetadata(
-      FeedId.fromTrusted(feedId),
-    );
-    return Object.values(metadata?.unsubscribe ?? {});
-  } catch (error) {
-    logger.error("Error reading unsubscribe URLs", {
-      feedId,
-      error: String(error),
-    });
-    return [];
-  }
-}
-
-export async function purgeFeedKeysStep(
-  emailStorage: KVNamespace,
-  feedId: string,
-  options: { cursor?: string; limit?: number; bucket?: R2Bucket } = {},
-): Promise<{
-  deletedKeys: string[];
-  failedKeys: string[];
-  cursor: string;
-  listComplete: boolean;
-}> {
-  const repo = new FeedRepository(emailStorage);
-  const id = FeedId.fromTrusted(feedId);
-  const listed = await repo.listFeedKeys(id, {
-    cursor: options.cursor,
-    limit: options.limit,
-  });
-  const keys = listed.names;
-
-  if (options.bucket && keys.length > 0) {
-    const emailKeys = keys.filter((k) => repo.isEmailKey(id, k));
-    if (emailKeys.length > 0) {
-      const emailDataResults = await Promise.allSettled(
-        emailKeys.map((k) => repo.getEmail(k)),
-      );
-      const attachmentIds = emailDataResults
-        .filter(
-          (r): r is PromiseFulfilledResult<EmailData | null> =>
-            r.status === "fulfilled",
-        )
-        .flatMap((r) => r.value?.attachments?.map((a) => a.id) ?? []);
-      if (attachmentIds.length > 0) {
-        await Promise.allSettled(
-          attachmentIds.map((id) => options.bucket!.delete(id)),
-        );
-      }
-    }
-  }
-
-  const { ok, failed } = await deleteKeysWithConcurrency(
-    emailStorage,
-    keys,
-    35,
-  );
-
-  return {
-    deletedKeys: ok,
-    failedKeys: failed,
-    cursor: listed.cursor,
-    listComplete: listed.listComplete,
-  };
-}
-
-export async function purgeExpiredFeeds(
-  emailStorage: KVNamespace,
-  feedId: string,
-  bucket?: R2Bucket,
-): Promise<void> {
-  let cursor: string | undefined;
-  do {
-    const step = await purgeFeedKeysStep(emailStorage, feedId, {
-      bucket,
-      limit: 100,
-      cursor,
-    });
-    cursor = step.listComplete ? undefined : step.cursor;
-  } while (cursor);
-}