Review fixes: geo dedup and geoDM names in recent chats

- A person still visible in the geohash roster could also get a recent
  chat row (the builder only subtracted mesh rows). Visible geohash
  pubkeys now join the identity set via their PeerID(nostr_:) form, so
  the absent-from-rosters contract holds on location channels too.
- GeoDM rows went through resolveNickname, which only consults mesh
  identity sources and rendered nostr_… keys as an opaque anon
  fallback. They now resolve through geohashDisplayName (Nostr key
  mapping, bare-key fallback).

Both pinned in the recent-chats architecture test.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

bitchat/App/PeerListModel.swift

@@ -265,7 +265,7 @@ final class PeerListModel: ObservableObject {
 
         let geohashPeople = buildGeohashPeople()
         let groupRows = buildGroupRows()
-        let recentChatRows = buildRecentChatRows(meshRows: meshRows)
+        let recentChatRows = buildRecentChatRows(meshRows: meshRows, geohashPeople: geohashPeople)
 
         self.meshRows = meshRows
         reachableMeshPeerCount = meshCounts.reachable
@@ -295,7 +295,10 @@ final class PeerListModel: ObservableObject {
     /// mirrored under both an ephemeral and a stable peer ID collapse to
     /// one row per identity (newest activity wins), matching how the
     /// private-chat coordinators consolidate on open.
-    private func buildRecentChatRows(meshRows: [MeshPeerRow]) -> [RecentChatRow] {
+    private func buildRecentChatRows(
+        meshRows: [MeshPeerRow],
+        geohashPeople: [GeohashPersonRow]
+    ) -> [RecentChatRow] {
         // A conversation can be keyed by the stable Noise peer ID while the
         // roster lists the ephemeral one — compare fingerprints too.
         var visibleIdentities = Set<String>()
@@ -305,6 +308,12 @@ final class PeerListModel: ObservableObject {
                 visibleIdentities.insert(fingerprint)
             }
         }
+        // Someone visible in the geohash section must not also get a chat
+        // row: their GeoDM conversation is keyed by the nostr_ form of the
+        // same pubkey the roster lists.
+        for person in geohashPeople {
+            visibleIdentities.insert(PeerID(nostr_: person.id).id)
+        }
 
         struct Candidate {
             let peerID: PeerID
@@ -337,13 +346,23 @@ final class PeerListModel: ObservableObject {
             .map { candidate in
                 RecentChatRow(
                     peerID: candidate.peerID,
-                    displayName: chatViewModel.resolveNickname(for: candidate.peerID),
+                    displayName: displayName(for: candidate.peerID),
                     hasUnread: chatViewModel.hasUnreadMessages(for: candidate.peerID),
                     lastActivity: candidate.lastActivity
                 )
             }
     }
 
+    /// GeoDM conversations resolve through the Nostr mapping —
+    /// `resolveNickname` only consults mesh identity sources and would
+    /// render a `nostr_…` key as an opaque `anonnost` fallback.
+    private func displayName(for peerID: PeerID) -> String {
+        if peerID.isGeoDM {
+            return chatViewModel.geohashDisplayName(for: peerID)
+        }
+        return chatViewModel.resolveNickname(for: peerID)
+    }
+
     private static func changedConversationID(_ change: ConversationChange) -> ConversationID {
         switch change {
         case .appended(let id, _),

bitchatTests/AppArchitectureTests.swift

@@ -506,6 +506,40 @@ struct AppArchitectureTests {
         #expect(peerListModel.recentChatRows.first?.lastActivity == Date(timeIntervalSince1970: 100))
         // The roster doesn't list this peer — that's exactly why the row exists.
         #expect(!peerListModel.meshRows.contains { $0.peerID == offlinePeerID })
+
+        // A geoDM thread resolves through the Nostr mapping (bare-key
+        // fallback here), never resolveNickname's mesh-only anon fallback.
+        let pubkeyHex = String(repeating: "ab", count: 32)
+        let geoDMPeer = PeerID(nostr_: pubkeyHex)
+        viewModel.seedPrivateChat([
+            BitchatMessage(
+                id: "geo-1",
+                sender: "stranger",
+                content: "hello from another cell",
+                timestamp: Date(timeIntervalSince1970: 300),
+                isRelay: false,
+                isPrivate: true,
+                recipientNickname: "me",
+                senderPeerID: geoDMPeer
+            )
+        ], for: geoDMPeer)
+
+        await waitUntil {
+            peerListModel.recentChatRows.contains { $0.peerID == geoDMPeer }
+        }
+        let geoRow = peerListModel.recentChatRows.first { $0.peerID == geoDMPeer }
+        #expect(geoRow?.displayName == geoDMPeer.bare)
+
+        // While that person is visible in the geohash roster, the chat row
+        // collapses — same absent-from-rosters contract as mesh.
+        viewModel.participantTracker.setActiveGeohash("u4pruy")
+        viewModel.participantTracker.recordParticipant(pubkeyHex: pubkeyHex, geohash: "u4pruy")
+
+        await waitUntil {
+            !peerListModel.recentChatRows.contains { $0.peerID == geoDMPeer }
+        }
+        #expect(!peerListModel.recentChatRows.contains { $0.peerID == geoDMPeer })
+        #expect(peerListModel.recentChatRows.map(\.peerID) == [offlinePeerID])
     }
 
     @Test("PrivateConversationModel resolves canonical header state for the selected DM")