android/ui: sort self peer first in list of peers

Closes tailscale/corp#19111

Signed-off-by: Percy Wegmann <percy@tailscale.com>

android/src/main/java/com/tailscale/ipn/ui/model/TailCfg.kt

@@ -101,6 +101,8 @@ class Tailcfg {
     val displayName: String
       get() = ComputedName ?: Name
 
+    fun isSelfNode(netmap: Netmap.NetworkMap): Boolean = StableID == netmap.SelfNode.StableID
+
     fun connectedOrSelfNode(nm: Netmap.NetworkMap?) =
         Online == true || StableID == nm?.SelfNode?.StableID
 

android/src/main/java/com/tailscale/ipn/ui/util/PeerHelper.kt

@@ -39,7 +39,18 @@ class PeerCategorizer {
         grouped
             .map { (userId, peers) ->
               val profile = netmap.userProfile(userId)
-              PeerSet(profile, peers.sortedBy { it.ComputedName })
+              PeerSet(
+                  profile,
+                  peers.sortedWith { a, b ->
+                    when {
+                      a.StableID == b.StableID -> 0
+                      a.isSelfNode(netmap) -> -1
+                      b.isSelfNode(netmap) -> 1
+                      else ->
+                          (a.ComputedName?.lowercase() ?: "").compareTo(
+                              b.ComputedName?.lowercase() ?: "")
+                    }
+                  })
             }
             .sortedBy {
               if (it.user?.ID == me?.ID) {