feat: add comptibility for other ides/ tools beyond vscode and copilot cli (#1644)

Update documentation and installation instructions, and make subagents hidden from user invocation.

plugins/gem-team/.github/plugin/plugin.json

@@ -1,6 +1,6 @@
 {
   "name": "gem-team",
-  "version": "1.16.0",
+  "version": "1.20.0",
   "description": "Self-Learning Multi-agent orchestration harness for spec-driven development and automated verification.",
   "author": {
     "name": "mubaidr",