fix: remove duplicate version key from plugin.json and modernize for-in loop in lib.js

- plugin.json contained duplicate "version" keys ("0.1.0" then "0.2.0"); JSON parsers take the last value so it appeared to work, but this is invalid per spec and a maintenance hazard.
- findActiveExitNode used legacy for-in + hasOwnProperty guard; replaced with Object.keys() for modern, safe iteration (now consistent with parsePeers and the rest of lib.js).
- All 36 unit tests pass after the change.

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

tailscalectl/lib.js

@@ -24,8 +24,7 @@ function makeExitNodeCommand(hostname) {
 
 function findActiveExitNode(peerMap) {
     if (!peerMap) { return ""; }
-    for (const key in peerMap) {
-        if (!Object.prototype.hasOwnProperty.call(peerMap, key)) { continue; }
+    for (const key of Object.keys(peerMap)) {
         const p = peerMap[key];
         if (p.ExitNode) {
             return p.HostName || key;

tailscalectl/plugin.json

@@ -2,7 +2,6 @@
   "id": "tailscalectl",
   "name": "Tailscale",
   "description": "Tailscale status and controls on the Dank Bar",
-  "version": "0.1.0",
   "author": "John Morris",
   "icon": "vpn_key",
   "type": "widget",