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

setup/emulator/emulator

@@ -0,0 +1,17 @@
+#!/bin/sh
+# Launcher for the Polaris emulator.
+# Place at /var/www/emulator/Emulator/target/emulator and chmod +x.
+# Update the JAR name to match the version built by `mvn clean package`.
+
+file_name_emulator=emulator.log
+current_time=$(date "+%H%M_%d-%m-%Y")
+file_name=$file_name_emulator.$current_time
+
+# Rotate the previous log
+mkdir -p /var/log/emu
+mv /var/log/emu/emulator.log /var/log/emu/$file_name 2>/dev/null || true
+
+# -Xmx4096m = 4 GB. 1 GB=1024, 2 GB=2048, 3 GB=3072, 4 GB=4096
+java -Dfile.encoding=UTF8 -Xmx4096m \
+  -jar /var/www/emulator/Emulator/target/Habbo-*-jar-with-dependencies.jar \
+  >/var/log/emu/emulator.log