3dom4wf7p: Poll the feed before reporting a publish failure

A freshly published post can take a moment to surface on the home feed, so
the single immediate confirm reload reported a false failure even though the
post went through. Retry the reload a few times; once the server has accepted
the publish, treat a not-yet-visible post as success instead of an error.

tests/post.test.ts

@@ -6,6 +6,7 @@ import { POST } from "@/app/api/posts/route";
 import { Composer } from "@/components/Composer";
 import { FeedView } from "@/components/FeedView";
 import { PostError, publishAndConfirm, sendPost } from "@/lib/post-client";
+import { FeedLoadError } from "@/lib/feed-client";
 import { createSession } from "@/lib/session-store";
 
 function session() {
@@ -84,14 +85,42 @@ describe("publishAndConfirm", () => {
     expect(state.id).toBeNull();
   });
 
-  it("throws and keeps the id when the post is not on the page, then a retry does not create again", async () => {
+  const nap = { delayMs: 0, sleep: async () => {} };
+
+  it("retries the reload and succeeds once a slow post surfaces", async () => {
     const state = { id: null as string | null };
     const send = vi.fn(async () => "p9");
-    const miss = async () => ({ items: [item("p1")], nextCursor: null });
-    await expect(publishAndConfirm("hi", null, state, { send, fetchPage: miss })).rejects.toBeInstanceOf(PostError);
+    let n = 0;
+    const fetchPage = vi.fn(async () =>
+      n++ < 2 ? { items: [item("p1")], nextCursor: null } : { items: [item("p9"), item("p1")], nextCursor: null },
+    );
+    const got = await publishAndConfirm("hi", null, state, { send, fetchPage, confirm: nap });
+    expect(got.items.map((i) => (i as { post: { id: string } }).post.id)).toContain("p9");
+    expect(state.id).toBeNull();
+    expect(send).toHaveBeenCalledTimes(1);
+    expect(n).toBe(3);
+  });
+
+  it("does not throw or duplicate when a published post never surfaces (feed lag)", async () => {
+    const state = { id: null as string | null };
+    const send = vi.fn(async () => "p9");
+    const miss = vi.fn(async () => ({ items: [item("p1")], nextCursor: null }));
+    const got = await publishAndConfirm("hi", null, state, { send, fetchPage: miss, confirm: { ...nap, attempts: 3 } });
+    expect(got).toBeTruthy();
+    expect(state.id).toBeNull();
+    expect(send).toHaveBeenCalledTimes(1);
+  });
+
+  it("keeps the id when the reload itself fails, so a retry re-checks without creating again", async () => {
+    const state = { id: null as string | null };
+    const send = vi.fn(async () => "p9");
+    const boom = async () => {
+      throw new FeedLoadError(false);
+    };
+    await expect(publishAndConfirm("hi", null, state, { send, fetchPage: boom, confirm: nap })).rejects.toBeInstanceOf(PostError);
     expect(state.id).toBe("p9");
     const hit = async () => ({ items: [item("p9")], nextCursor: null });
-    await publishAndConfirm("hi", null, state, { send, fetchPage: hit });
+    await publishAndConfirm("hi", null, state, { send, fetchPage: hit, confirm: nap });
     expect(send).toHaveBeenCalledTimes(1);
   });