feat: added http header input

Author: raphael-goetz

definitions/http/data_type/http.header_input.proto.json

@@ -0,0 +1,24 @@
+{
+  "variant": "OBJECT",
+  "identifier": "HTTP_HEADER_INPUT",
+  "name": [
+    {
+      "code": "en-US",
+      "content": "HTTP Headers"
+    }
+  ],
+  "alias": [
+    {
+      "code": "en-US",
+      "content": "http;header;entry;input"
+    }
+  ],
+  "displayMessage": [
+    {
+      "code": "en-US",
+      "content": "HTTP Headers"
+    }
+  ],
+  "rules": [],
+  "genericKeys": []
+}