increase ram to 4gb during build

add optional coingecko env keys

frontend/public/json/ghostfolio.json

@@ -18,7 +18,7 @@
       "script": "ct/ghostfolio.sh",
       "resources": {
         "cpu": 2,
-        "ram": 2048,
+        "ram": 4096,
         "hdd": 8,
         "os": "debian",
         "version": "12"
@@ -41,6 +41,14 @@
     {
       "text": "Configuration file: `/opt/ghostfolio/.env`",
       "type": "info"
+    },
+    {
+      "text": "Optional: CoinGecko API keys can be added during installation or later in the .env file for enhanced cryptocurrency data.",
+      "type": "info"
+    },
+    {
+      "text": "Build process requires 4GB RAM (runtime: ~2GB). A temporary swap file will be created automatically if insufficient memory is detected.",
+      "type": "warning"
     }
   ]
 }