Fast-poll Tailscale and Dropbox at shell startup so icons go live promptly

Both services fire one status poll when the shell starts, but after a fresh
boot that lands before tailscaled has connected or dropboxd has finished its
respawn dance, leaving the bar icons stale for a full 30s/60s refresh
interval. Re-poll every 2s until the service shows up (or ~30s pass), then
hand off to the normal periodic refresh.

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

shell/plugins/panels/tailscale/Service.qml

@@ -363,6 +363,22 @@ Item {
     onTriggered: root.refresh()
   }
 
+  Timer {
+    // After a fresh boot the startup poll usually lands before tailscaled has
+    // connected, which left the icon stale until the next periodic refresh.
+    // Poll quickly until the service shows up, or give up after ~30 seconds.
+    id: startupRamp
+    property int ticks: 0
+    interval: 2000
+    repeat: true
+    running: true
+    onTriggered: {
+      ticks += 1
+      if (root.running || ticks >= 15) startupRamp.running = false
+      else root.refresh()
+    }
+  }
+
   Timer {
     id: delayedRefresh
     interval: 600