Group names survive a reinstall, and reach our own other devices

Two gaps the group-name change left behind.

The encrypted history export carried the messages but not the names. That
was harmless while the relay answered with them — a reinstalled device got
them back for free. It holds none now, so this device's copy is the only
copy, and restoring a backup would have produced a chat list of groups all
called "Group": exactly the loss the export exists to prevent. Names ride
the payload, and only fill gaps on import — a backup is older than the
device by definition, so a rename made since must not be undone.

And fan-out excludes our own account, so a second phone we own was told by
nobody: the relay has no name to serve it and the members only send to each
other. The announcement now addresses our own account too. The fan-out loop
already skipped our own device, so what goes out reaches our OTHER devices
and nothing else.

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

client/src/main/kotlin/io/flamenet/client/Conversations.kt

@@ -1312,8 +1312,13 @@ class Conversations(
         val key = vault.loadDelivery()?.key ?: return
         val payload = SealedSender.deliveryKeyEnvelope(
             key, groupId = groupId, groupName = name)
-        for (member in memberIds) {
-            if (member == myUserId) continue
+        // 🔴 **Our own account is included, and that is the point.** Fan-out
+        // excludes us everywhere else, so a second phone we own would be told
+        // by nobody: the relay has no name to serve it and the members only
+        // send to each other. The fan-out loop already skips our own device
+        // ("never talk to ourselves"), so what goes out is addressed to our
+        // OTHER devices and to nothing else.
+        for (member in memberIds + listOfNotNull(myUserId)) {
             runCatching { sendPlaintext(member, payload) }
         }
     }

client/src/test/kotlin/io/flamenet/client/GroupNameTest.kt

@@ -232,6 +232,45 @@ class GroupNameTest {
         assertEquals(0, server.requestCount)
     }
 
+    // -- Surviving a reinstall -------------------------------------------------
+
+    /**
+     * 🔴 **A restored backup must bring the group names with it.** The relay
+     * used to answer with the name, so a reinstalled device got it back for
+     * free; it holds none now, which makes the device's copy the only copy. An
+     * export carrying the messages but not the names restores a chat list of
+     * groups all called "Group" — the exact loss the export exists to stop.
+     */
+    @Test
+    fun `an exported backup carries group names into a fresh device`() {
+        val old = vault()
+        old.saveGroupName("g1", "Book club")
+        val payload = old.exportPayload()
+
+        val fresh = vault()
+        assertNull(fresh.groupName("g1"))
+        fresh.mergeImportedPayload(payload, 0.0)
+
+        assertEquals("Book club", fresh.groupName("g1"))
+    }
+
+    /**
+     * ⚠️ A backup is older than the device by definition. A rename made since
+     * the export must not be undone by restoring it.
+     */
+    @Test
+    fun `a restored backup does not overwrite a newer name`() {
+        val old = vault()
+        old.saveGroupName("g1", "Book club")
+        val payload = old.exportPayload()
+
+        val current = vault()
+        current.saveGroupName("g1", "Book club, Tuesdays")
+        current.mergeImportedPayload(payload, 0.0)
+
+        assertEquals("Book club, Tuesdays", current.groupName("g1"))
+    }
+
     // -- Where it is kept ------------------------------------------------------
 
     @Test