Fix geohash filtering (#376)

* fix(geohash): enforce client-side filter on subscription and validate 'g' tag in handler; move dedup after validation; avoid misrouting events across geohashes

* cleanup duplicate code block

* remove

app/src/main/java/com/bitchat/android/nostr/NostrRelayManager.kt

@@ -666,6 +666,16 @@ class NostrRelayManager private constructor() {
                     relay?.messagesReceived = (relay?.messagesReceived ?: 0) + 1
                     updateRelaysList()
                     
+                    // CLIENT-SIDE FILTER ENFORCEMENT: Ensure this event matches the subscription's filter
+                    activeSubscriptions[response.subscriptionId]?.let { subInfo ->
+                        val matches = try { subInfo.filter.matches(response.event) } catch (e: Exception) { true }
+                        if (!matches) {
+                            Log.v(TAG, "🚫 Dropping event ${response.event.id.take(16)}... not matching filter for sub=${response.subscriptionId}")
+                            // Do NOT call deduplicator here to allow the correct subscription to process it later
+                            return
+                        }
+                    }
+                    
                     // DEDUPLICATION: Check if we've already processed this event
                     val wasProcessed = eventDeduplicator.processEvent(response.event) { event ->
                         // Only log non-gift-wrap events to reduce noise