Provide the metadata for tooling that cares about executing zap and supports the JSON-based metaformat. (#1550)

* add slt metadata

* add function

Author: paulr34

apack.json

@@ -50,7 +50,19 @@
       "exe": "src-script/zap-start.js"
     }
   },
+  "ui": {
+    "launchItem": {
+      "id": "ZAP",
+      "category": "tools",
+      "label": "ZCL Advanced Platform",
+      "launchUiFunction": "launchZAP",
+      "toolTip": "ZCL Advanced Platform"
+    }
+  },
   "function": {
+    "launchZAP": {
+      "cmd": "$(zap)"
+    },
     "ui:uc_cli": {
       "cmd": "$(zap)"
     },