feat(insights): read location context from Apollo (#177)

The local location_history table is a one-time Takeout import: it ends
in 2019, still has the ghost-device and coarse cell-fix samples Apollo
has since excluded, and was read loosely. The per-photo line took the
nearest sample within +/-3 h at any distance (17% of photo moments got a
position >2 km away), and get_location_history listed the first 20 rows
of a +/-14-day window sorted ascending (always ~14 days before the date).

With APOLLO_API_BASE_URL set:
- per-photo context comes from /api/location/at (30 min max gap; no
  sample -> no line). A Place stay renders as "at Home (14:02-18:30)" in
  the display zone; an unnamed sample is reverse-geocoded.
- get_location_history returns Apollo's /api/location/day timeline for
  the date (+/-1 day at most), and is offered even with an empty local
  table.

Both fall back to the local table when Apollo is unset or a call fails;
the local tool path now covers the requested local day(s) and samples
evenly instead of listing a window's first rows.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

migrations/2026-10-17-000000_reresolve_implausible_utc_dates/down.sql

@@ -1,3 +0,0 @@
--- Data fix only: the cleared instants were wrong and are re-resolved by the
--- drain, so there is nothing to restore.
-SELECT 1;

migrations/2026-10-17-000000_reresolve_implausible_utc_dates/up.sql

@@ -1,17 +0,0 @@
--- #160 follow-up. The first fix (2026-10-16 migration) cleared rows whose
--- legacy `date_taken_source` was 'filename'. But the true-instant drain
--- (#118) re-ran the resolver over rows with a correct legacy date (e.g. an
--- exiftool container date) and wrote only the new-contract triple, so
--- some rows carry a filename-derived implausible year in `date_utc` while
--- their legacy pair says 'exiftool'. On prod: three VID_<counter> videos
--- (years 2095, 2229, 8580) whose containers say 2016/2017.
---
--- Clear just the triple on any row whose true instant is outside
--- [1995-01-01, 2028-01-01) UTC. `date_utc IS NULL` puts it back in
--- `backfill_utc_dates`, which re-resolves it with the gated matcher; the
--- legacy pair is left alone (it's frozen for rollback, and here correct).
-UPDATE image_exif
-SET date_utc = NULL,
-    camera_offset_minutes = NULL,
-    date_taken_tz_source = NULL
-WHERE date_utc < 788918400 OR date_utc >= 1830297600;

src/filename_audit.rs

@@ -495,92 +495,18 @@ mod tests {
         assert_eq!(rels, vec!["Screenshot_2014-06-01-20-44-50.png"]);
     }
 
-    /// A connection migrated up to (not including) the migration whose
-    /// name contains `name`, for seeding the state a data fix repairs.
-    fn conn_before_migration(name: &str) -> SqliteConnection {
-        let mut conn = SqliteConnection::establish(":memory:").expect("in-memory sqlite");
-        for m in conn.pending_migrations(DB_MIGRATIONS).expect("pending") {
-            if m.name().to_string().contains(name) {
-                break;
-            }
-            conn.run_migration(&*m).expect("migration");
-        }
-        conn
-    }
-
-    #[test]
-    fn migration_clears_implausible_true_instants_but_keeps_legacy_dates() {
-        // The prod shape the first fix missed: a correct exiftool legacy
-        // date, with a filename-derived 2229 instant written by the drain.
-        let mut conn = conn_before_migration("reresolve_implausible_utc_dates");
-        seed_row(
-            &mut conn,
-            1,
-            "VID_22290524_080551_818.mp4",
-            Some(1_500_069_534),
-            Some("exiftool"),
-        );
-        seed_row(&mut conn, 1, "beach.jpg", Some(1_500_069_534), Some("exif"));
-        let set_utc = |conn: &mut SqliteConnection, path: &str, utc: i64| {
-            diesel::update(image_exif::table.filter(image_exif::rel_path.eq(path)))
-                .set((
-                    image_exif::date_utc.eq(utc),
-                    image_exif::camera_offset_minutes.eq(-300),
-                    image_exif::date_taken_tz_source.eq("assumed_server"),
-                ))
-                .execute(conn)
-                .unwrap();
-        };
-        set_utc(&mut conn, "VID_22290524_080551_818.mp4", 8_185_669_551);
-        set_utc(&mut conn, "beach.jpg", 1_500_069_534);
-
-        conn.run_pending_migrations(DB_MIGRATIONS)
-            .expect("fix migration");
-
-        type Row = (
-            String,
-            Option<i64>,
-            Option<String>,
-            Option<i64>,
-            Option<i32>,
-        );
-        let rows: Vec<Row> = image_exif::table
-            .select((
-                image_exif::rel_path,
-                image_exif::date_taken,
-                image_exif::date_taken_source,
-                image_exif::date_utc,
-                image_exif::camera_offset_minutes,
-            ))
-            .order(image_exif::rel_path)
-            .load(&mut conn)
-            .unwrap();
-        assert_eq!(
-            rows,
-            vec![
-                (
-                    "VID_22290524_080551_818.mp4".into(),
-                    Some(1_500_069_534),
-                    Some("exiftool".into()),
-                    None,
-                    None
-                ),
-                (
-                    "beach.jpg".into(),
-                    Some(1_500_069_534),
-                    Some("exif".into()),
-                    Some(1_500_069_534),
-                    Some(-300)
-                ),
-            ]
-        );
-    }
-
     #[test]
     fn migration_clears_implausible_filename_dates_for_re_resolution() {
         // Migrate up to just before the #160 data fix, seed rows as the
         // old matcher left them, then apply it.
-        let mut conn = conn_before_migration("reresolve_implausible_filename_dates");
+        const FIX: &str = "reresolve_implausible_filename_dates";
+        let mut conn = SqliteConnection::establish(":memory:").expect("in-memory sqlite");
+        for m in conn.pending_migrations(DB_MIGRATIONS).expect("pending") {
+            if m.name().to_string().contains(FIX) {
+                break;
+            }
+            conn.run_migration(&*m).expect("migration");
+        }
         // 2229-05-24 08:05:51 and 1053-05-19 10:15:27 (wall-as-UTC), a
         // real 2014 filename date, and an fs_time row that isn't ours to
         // touch even though its date is odd.