Local-first Brief: the landing leads with good news from your home

Per the owner's call (overrides the earlier "Brief sacred" stance): when a home is
set, the homepage opens with local good news first, not global. This is the hook —
you land and see awesome stories from YOUR corner first.

- queries.home_brief: local-first highlights (high/medium-confidence near, blended
  out to country then world so it's always a full, strong set), preferring already-
  summarized stories so the calm read stays rich. Recent window, ranked within tier.
- /api/brief gains a `home` param: private/no-store when set; over-fetches + caps so
  dismissal/boundary filtering never thins it; falls back to global top-up if needed.
- Landing UI: a Local <-> Global toggle ("📍 Near you / 🌍 Everywhere") when a home
  is set, the calm picker invite when not (dismissible), and Change. Default leads
  local; one tap back to the global brief. No home set => exactly today's behavior.

Backend + frontend tests green.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

tests/test_geo_feed.py

@@ -81,6 +81,21 @@ def test_country_only_home_gates_near_on_confidence(app_db):
     assert a5["section"] == "world"                      # low-conf home-country -> world, not vanished
 
 
+def test_home_brief_leads_with_local(app_db):
+    # The landing's /api/brief?home=US-NY leads with high-confidence NY good news,
+    # tags items by section, and titles it "Close to home". The low-conf NY story (#5)
+    # is not elevated as local.
+    r = TestClient(app_db).get("/api/brief?home=US-NY&limit=10").json()
+    assert r["title"] == "Close to home"
+    near_ids = {it["id"] for it in r["items"] if it["section"] == "near"}
+    assert near_ids == {1, 2, 3, 4}                       # the high-conf NY stories
+    # near items all appear before any world item (local leads)
+    secs = [it["section"] for it in r["items"]]
+    if "near" in secs and "world" in secs:
+        assert max(i for i, s in enumerate(secs) if s == "near") < \
+               min(i for i, s in enumerate(secs) if s == "world")
+
+
 def test_no_home_is_unchanged_and_unsectioned(app_db):
     r = TestClient(app_db).get("/api/feed?limit=50").json()
     assert all(it["section"] is None for it in r["items"])