为什么这张 Tikz 图片会导致无限循环？

Question

不知何故，以下 Latex 代码无法在 TexStudio 中完成编译，至少在我的 PC 上是这样。（这会导致无限的构建过程，我希望我的意思很清楚。）你能解释一下我做错了什么吗？

\documentclass[a4paper, 11pt, oneside]{book}
\bibliographystyle{plainnat}


\makeatletter
\makeatother
\usepackage[a4paper,left=3cm,right=3cm,top=3cm,bottom=3cm]{geometry}

\usepackage{amsfonts}
\usepackage{amsmath}
\usepackage{amssymb}
\usepackage{amsthm}
\usepackage[style=numeric,firstinits,sorting=none]{biblatex}
\usepackage{dialogue}
\usepackage{enumitem}
\usepackage{etoolbox}
\usepackage{fancyhdr}
\usepackage[T1]{fontenc}
\usepackage{graphicx}
\usepackage[utf8]{inputenc}
\usepackage{latexsym}
\usepackage{lmodern}    % The Font Type
\usepackage{mathtools}
\usepackage{mdframed}
\usepackage{pgf}
\usepackage{siunitx}
\usepackage{tcolorbox}
\usepackage[flushleft]{threeparttable}
\usepackage{tikz}
\usepackage{tikzpeople}
\usepackage{titlesec}
\usepackage[absolute,overlay]{textpos}
\usepackage{wrapfig}
\usepackage{xcolor}
\usepackage{xspace}



\titleformat{\chapter}{\bfseries \centering}{\huge \Roman{chapter}.}{10pt}{\huge}
\titleclass{\chapter}{straight}







\begin{document}



Some text.


                 \begin{tikzpicture}[scale=0.5]
                                    \draw (0,0) -- (4.5,0) -- (4.5,4.5) -- (0,4.5) -- (0,0)
                                    \draw (1.5,0) -- (3,0) -- (3,1.5) -- (1.5,1.5) -- (1.5,0);
                                    \draw (2.25,0) -- (2.25,1.5);
                                    \draw (1.5,0.75) -- (3,0.75);
                                    %
                                    \filldraw[red] (2.5,0.4) circle (2pt) node [below] {$z$};
                                    \draw[red]  (2.5,0.4) -- (3,0);
                                    \filldraw[black] (0,0) circle (2pt);
                                    \filldraw[black] (1.5,0) circle (2pt);
                                    \filldraw[black] (3,0) circle (2pt) node [below right] {$z$};
                                    \filldraw[black] (4.5,0) circle (2pt);
                                    \filldraw[black] (0,1.5) circle (2pt);
                                    \filldraw[black] (1.5,1.5) circle (2pt);
                                    \filldraw[black] (3,1.5) circle (2pt);
                                    \filldraw[black] (4.5,1.5) circle (2pt);
                                    \filldraw[black] (0,-1.5) circle (2pt);
                                    \filldraw[black] (1.5,-1.5) circle (2pt);
                                    \filldraw[black] (3,-1.5) circle (2pt);
                                    \filldraw[black] (4.5,-1.5) circle (2pt);
                                    \filldraw[black] (0,3) circle (2pt);
                                    \filldraw[black] (1.5,3) circle (2pt);
                                    \filldraw[black] (3,3) circle (2pt);
                                    \filldraw[black] (4.5,3) circle (2pt);
                \end{tikzpicture}


\end{document}