feat: add guided /gw-triage:setup for Jira token

Replaces the manual shell-profile steps in the README: the skill
verifies the token before saving it to ~/.claude/settings.json env,
where Claude Code injects it shell-independently.

.claude-plugin/plugin.json

@@ -1,7 +1,7 @@
 {
   "name": "gw-triage",
   "description": "Da screenshot + messaggio Telegram a issue Jira instradata al dev giusto",
-  "version": "0.1.1",
+  "version": "0.2.0",
   "author": {
     "name": "GrowingWay"
   }