fix: make git clone operations idempotent in install.sh

Add clone_or_update helper function that checks if the target directory
exists before cloning. If the directory exists, it pulls the latest
changes instead of failing. This allows the install script to be re-run
safely without crashing on existing repositories.

Author: santosomar

install.sh

@@ -115,11 +115,26 @@ sudo systemctl enable docker --now
 #--------------------------------------------------
 echo "[+] Cloning GitHub repos..."
 cd /root
-git clone https://github.com/The-Art-of-Hacking/h4cker.git
-git clone https://github.com/danielmiessler/SecLists.git
-git clone https://github.com/internetwache/GitTools.git
-git clone https://github.com/swisskyrepo/PayloadsAllTheThings.git
-git clone https://github.com/The-Art-of-Hacking/websploit.git
+
+# Helper function to clone or update a repo
+clone_or_update() {
+    local repo_url="$1"
+    local dir_name=$(basename "$repo_url" .git)
+    
+    if [ -d "$dir_name" ]; then
+        echo "[*] Directory '$dir_name' already exists. Pulling latest changes..."
+        cd "$dir_name" && git pull && cd ..
+    else
+        echo "[+] Cloning $repo_url..."
+        git clone "$repo_url"
+    fi
+}
+
+clone_or_update https://github.com/The-Art-of-Hacking/h4cker.git
+clone_or_update https://github.com/danielmiessler/SecLists.git
+clone_or_update https://github.com/internetwache/GitTools.git
+clone_or_update https://github.com/swisskyrepo/PayloadsAllTheThings.git
+clone_or_update https://github.com/The-Art-of-Hacking/websploit.git
 
 # IoT firmware exercises for reverse engineering courses
 mkdir -p /root/iot_exercises