Add the ability for the ScopeResolver to escape the "."

The "." means that we want to go a level deeper for the location
of the relative autocomplete, something like ".a.b", but in
a lot of cases "." is actually part of the internal endpoint
name and so we need to respect that to resolve correctly.

src/plugins/console/public/lib/autocomplete/body_completer.js

@@ -79,7 +79,18 @@ class ScopeResolver extends SharedComponent {
       throw new Error('unsupported link format', this.link);
     }
 
-    let path = this.link.replace(/\./g, '{').split(/(\{)/);
+    let path = this.link
+      .replace(/[\\]?\./g, match => {
+        // An escaped '.' is collapsed to '.';
+        if (match.startsWith('\\')) {
+          return '.';
+        }
+        // If there is no leading '\' then replace the '.' with the noop '{' char
+        // for us to split this path on.
+        return '{';
+      })
+      .split(/(\{)/);
+
     const endpoint = path[0];
     let components;
     try {

src/plugins/console/server/lib/spec_definitions/json/overrides/cluster.put_settings.json

@@ -59,7 +59,7 @@
         }
       },
       "transient": {
-        "__scope_link": ".persistent"
+        "__scope_link": "cluster\\.put_settings.persistent"
       }
     }
   }