fix: the native path never reported tier-gated posts (milestone 387 step A1)

`make_run_stats` has always declared `tier_gated_count`, and
DownloadDetailModal has always rendered it. gallery-dl populated it;
`ingest_core._result` did not — it built run_stats with six keys and let
the seventh default to 0, while the very same walk counted gated posts
into `gated_skipped` and spent the number on a log line.

So on Patreon, SubscribeStar and pixiv — the three platforms we now own —
the Downloads modal read "Tier-gated: 0" for a walk that skipped N
paywalled posts. A creator we've lost access to was indistinguishable
from a creator who stopped posting. Migrating Patreon off gallery-dl is
what dropped the signal.

Pass the count through, and tick it in the live-progress payload too, so
a long backfill on an inaccessible creator explains itself while it runs
rather than only at finalization. ActiveDownloadsPanel renders it only
when non-zero, coloured 'info' to match the severity FailingSourcesCard
already assigns tier_limited — this is not a failure.

Tests assert the run_stats key the UI actually reads rather than the
ingester's internal counter, so the guard tracks the property and not a
name. Falsification is structural: `make_run_stats` defaults the key to
0, so both assertions fail against the pre-fix call.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01LNXXULQDjVZmbuNa2G9mD9

tests/test_patreon_ingester.py

@@ -678,6 +678,56 @@ async def test_gated_post_skipped_entirely_no_media_no_record(
     assert _count_ledger(sync_engine, source_id) == 2
 
 
+@pytest.mark.asyncio
+async def test_gated_posts_are_reported_in_run_stats(
+    source_id, sync_engine, tmp_path,
+):
+    """A gated post must be COUNTED, not just skipped.
+
+    `make_run_stats` has always declared `tier_gated_count` and
+    DownloadDetailModal has always rendered it, but the native path never
+    populated it — so a walk that skipped N paywalled posts reported 0, and a
+    creator we've lost access to looked exactly like a creator who stopped
+    posting. Asserted on the run_stats key the UI actually reads (not the
+    ingester's internal counter) so the guard tracks the property, not a name.
+    """
+    gated = [(f"g{i}", [_media(f"g{i}", 1)]) for i in range(3)]
+    am = _media("open", 1)
+    client = _FakeClient(
+        [(None, [*gated, ("open", [am])])],
+        gated={"g0", "g1", "g2"},
+    )
+    ing = _ingester(sync_engine, tmp_path, client, _FakeDownloader(tmp_path))
+
+    result = ing.run(
+        source_id=source_id, campaign_id="c1", artist_slug="ingest",
+        url="https://patreon.com/ingest", mode="backfill",
+    )
+
+    assert result.run_stats["tier_gated_count"] == 3
+    # Not conflated with the other skip tiers: seen/on-disk skips are a
+    # different fact from "we aren't allowed to see this".
+    assert result.run_stats["skipped_count"] == 0
+    assert result.run_stats["downloaded_count"] == 1
+
+
+@pytest.mark.asyncio
+async def test_run_stats_reports_zero_gated_when_nothing_is_gated(
+    source_id, sync_engine, tmp_path,
+):
+    """The counter reports a real zero on a clean walk — so a 0 in the UI means
+    'nothing was gated', not 'this path never counted'."""
+    client = _FakeClient([(None, [("p1", [_media("p1", 1)])])])
+    ing = _ingester(sync_engine, tmp_path, client, _FakeDownloader(tmp_path))
+
+    result = ing.run(
+        source_id=source_id, campaign_id="c1", artist_slug="ingest",
+        url="https://patreon.com/ingest", mode="backfill",
+    )
+
+    assert result.run_stats["tier_gated_count"] == 0
+
+
 @pytest.mark.asyncio
 async def test_recapture_does_not_refetch_seen_media_missing_from_disk(
     source_id, sync_engine, tmp_path,