Fix installer execution by using /root instead of /tmp

Root cause: /tmp is mounted with noexec flag preventing execution.

Changed TEMP_DIR from /tmp/acronis-install to /root/acronis-install
This allows the installer binary to execute properly.

Verified: mount shows /tmp with noexec option
Solution: Use /root which allows execution

modules/backup/acronis-install.sh

@@ -226,8 +226,8 @@ echo ""
 echo -e "${BOLD}Starting Installation...${NC}"
 echo ""
 
-# Create temp directory
-TEMP_DIR="/tmp/acronis-install-$$"
+# Create temp directory (not in /tmp as it may have noexec)
+TEMP_DIR="/root/acronis-install-$$"
 mkdir -p "$TEMP_DIR"
 cd "$TEMP_DIR" || exit 1