Triage cards expand to show every report behind a story

Cards showed a hard-capped 5 members with no way to see the rest. They now
render every report, with the first three inline and the remainder behind a
native <details> disclosure -- so it works without JavaScript and stays keyboard
accessible. Each entry carries its publication time and outlet, and the summary
names how many reports across how many outlets. `e` expands the selected card.

Loaded inline rather than through a lazy endpoint because the data is small:
measured on this corpus the largest cluster is 23 members and multi-item
clusters hold 249 between them.

Also fixes a bug this introduced. The sources-list comprehension was byte
identical in triage() and digest_page(), so a str.replace() intended for one hit
both, and digest_page started reading a published_at column its query does not
select -- four tests went red. The assert only checked that the anchor EXISTS,
not that it is UNIQUE. Edits now assert the occurrence count. The digest query
gained the column properly, since a timestamp is useful there too.

tests/test_delivery.py

@@ -267,3 +267,38 @@ def test_palette_is_defined_once_from_the_shared_partial(client, path):
     html = c.get(path).text
     assert html.count(".sitenav {") == 1
     assert html.count("--accent:#7c3aed") == 1, "light palette declared more than once"
+
+
+def test_triage_cards_expand_to_every_report(tmp_path, monkeypatch):
+    """A card must show all the reports behind a story, not a truncated slice."""
+    import numpy as np
+    from datetime import UTC, datetime
+
+    monkeypatch.setenv("NEWS_DB", str(tmp_path / "e.db"))
+    monkeypatch.setenv("NEWS_FEEDBACK_SECRET", SECRET)
+    con = store.connect(tmp_path / "e.db")
+    now = datetime.now(UTC)
+    for n in range(7):
+        store.upsert_source(con, id=f"s{n}", name=f"Outlet{n}", url=f"http://s{n}",
+                            kind="rss", bucket=f"b{n}", weight=1.0, prominence=0,
+                            enabled=1, poll_interval_secs=900)
+        con.execute("""INSERT INTO items (id,source_id,title,summary,url,canonical_url,
+                       published_at,first_seen_at,content_hash)
+                       VALUES (?,?,?,'',?,?,?,?,?)""",
+                    (f"i{n}", f"s{n}", f"Report number {n}", f"http://x/{n}",
+                     f"http://x/{n}", now.isoformat(), now.isoformat(), f"h{n}"))
+    con.execute("""INSERT INTO clusters (id,centroid,size,first_seen_at,last_seen_at,lead_item_id)
+                   VALUES ('big',?,7,?,?,'i0')""",
+                (store.to_blob(np.zeros(384, dtype="float32")),
+                 now.isoformat(), now.isoformat()))
+    for n in range(7):
+        con.execute("INSERT INTO cluster_members VALUES ('big',?,?)", (f"i{n}", now.isoformat()))
+
+    from news import web
+    web._VECTORS = None
+    html = TestClient(web.app).get("/").text
+
+    for n in range(7):
+        assert f"Report number {n}" in html, f"report {n} missing from the card"
+    assert "<details" in html and "4 more reports" in html
+    assert "across 7 outlets" in html