docs: add self-contained setup reference configs (emulator + nitro) and bold-link buttons

setup/nitro/client-mode.json

@@ -0,0 +1,8 @@
+{
+  "distObfuscationEnabled": false,
+  "secureAssetsEnabled": false,
+  "secureApiEnabled": false,
+  "apiBaseUrl": "https://MY_DOMAIN:2096",
+  "plainConfigBaseUrl": "https://MY_DOMAIN/configuration/",
+  "plainGamedataBaseUrl": "https://MY_DOMAIN/gamedata/"
+}