Bugfix/logical-flaw sweep: counting, races, baseline, pruning, RSSI

Root cause of the non-monotonic sighting count (60->29->63): MAC-rotating ecosystems mint a new tracker row per rotation, tracker rows were never pruned, and the UI re-sorts constantly, so different rows' counts read as one sequence. Compounded by no ingestion throttle and a lost-update race.

Fixes:
- ScanService: throttle the persisted path to <=1 sighting/device/15s (presence engine still sees every advert). Stops count inflation + DB hammering. @Volatile clone-alert ts; clear throttle map on stop.
- TrackerRepository: Mutex around record() (was a lost-update race: concurrent observations did get()->compute->upsert() with no lock). Always compute the co-movement assessment for display.
- VigilDatabase: prune stale non-approved tracker rows (were never deleted); +lastRssi/peakRssi/distinctPlaces/effectiveSightings for grounding; version 2.
- BaselineManager: count DWELL (one visit per 10-min window), not per-sighting. Old per-sighting count let a busy street or chatty tracker mint a fake 'home' in seconds and auto-trust a real stalker — a safety flaw.
- BleTrackerScanner: Apple filter now matches only Find My type 0x12, not every Apple device (iPhones/Watches/AirPods).
- UI: show distinct places + last RSSI on cards; detail sheet shows last/peak RSSI, distinct places, co-movement sightings, adverts logged; Active list filters to devices seen in the last 10 min so rotated identities drop off.
- Tests: CoMovementEvaluatorTest locks dedup, the RSSI gate, and the place/separated thresholds.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0187UiEtasyowhEBYs6s9iF5

app/src/main/kotlin/org/soulstone/vigil/detect/BaselineManager.kt

@@ -18,23 +18,29 @@ import org.soulstone.vigil.data.db.PlaceEntity
 object BaselineManager {
 
     const val DAY_MS = 86_400_000L
-    const val ANCHOR_MIN_VISITS = 60
+    const val DWELL_BUCKET_MS = 10 * 60_000L   // count at most one "visit" per 10-min dwell window
+    const val ANCHOR_MIN_VISITS = 18           // ~3h cumulative dwell before a cell counts as home/work
     const val BASELINE_MIN_DAYS = 3
 
-    /** Record a location fix in its cell; returns whether that cell is now an anchor. */
+    /**
+     * Note presence in a cell; returns whether it's an anchor. Crucially a cell
+     * accrues at most ONE visit per [DWELL_BUCKET_MS], so the anchor signal tracks
+     * time actually spent there — not how many trackers or adverts were seen.
+     *
+     * The previous per-sighting count was a real safety flaw: a busy street or a
+     * single chatty tracker could mint a fake "home" in seconds, which would then
+     * baseline-trust (silence alerts for) any tracker seen there — including a real
+     * stalking device.
+     */
     suspend fun noteLocation(placeDao: PlaceDao, geohash6: String, now: Long): Boolean {
-        val existing = placeDao.get(geohash6)
-        val visits = (existing?.visitCount ?: 0) + 1
+        val existing = placeDao.get(geohash6) ?: run {
+            placeDao.upsert(PlaceEntity(geohash6 = geohash6, visitCount = 1, lastSeen = now, anchor = false))
+            return false
+        }
+        if (now - existing.lastSeen < DWELL_BUCKET_MS) return existing.anchor
+        val visits = existing.visitCount + 1
         val anchor = visits >= ANCHOR_MIN_VISITS
-        placeDao.upsert(
-            PlaceEntity(
-                geohash6 = geohash6,
-                label = existing?.label ?: "",
-                visitCount = visits,
-                lastSeen = now,
-                anchor = anchor
-            )
-        )
+        placeDao.upsert(existing.copy(visitCount = visits, lastSeen = now, anchor = anchor))
         return anchor
     }
 }