fix: eliminate toggle decision staleness via poll-then-act (no cached desired state) (#42)

- toggleTailscale() now forces a fresh statusCheck instead of reading possibly-stale root.isConnected
- The actual up/down decision happens in statusCheck.onExited using the just-received value
- _pendingToggle is a transient one-shot flag (reset immediately after use) — not a persistent 'desired state' cache
- Complies with AGENTS.md rule 1 / #11

Written by AI agent working for @jtmorris. Model: Grok build-0.1.

tailscalectl/TailscaleWidget.qml

@@ -18,6 +18,7 @@ PluginComponent {
     property string _copyText: ""
     property string _copyCurrentTool: ""
     property int _copyAttempted: 0
+    property bool _pendingToggle: false  // transient one-shot for poll-then-act (#42) — reset immediately after use, no "desired state" cache
 
     layerNamespacePlugin: "tailscalectl"
     popoutWidth: 360
@@ -111,12 +112,21 @@ PluginComponent {
                 root.peers = []
                 ToastService.showError("tailscalectl", TailscaleLib.errorMessage("status"))
             }
+
+            // #42 poll-then-act: if a toggle was requested, use the *fresh* state we just received
+            if (root._pendingToggle) {
+                root._pendingToggle = false
+                toggleProcess.command = TailscaleLib.buildToggleCommand(root.isConnected)
+                toggleProcess.running = true
+            }
         }
     }
 
     function toggleTailscale() {
-        toggleProcess.command = TailscaleLib.buildToggleCommand(root.isConnected)
-        toggleProcess.running = true
+        // #42: poll-then-act — never decide up/down from potentially stale root.isConnected.
+        // Force a fresh statusCheck; the decision happens in its onExited using the just-received value.
+        root._pendingToggle = true
+        statusCheck.running = true
     }
 
     function setExitNode(hostname) {