feat: Implement core functionality for DTC C/C++ IDE

- Added ProjectManager class to handle project operations including opening, closing, building, and running projects.
- Introduced SyntaxHighlighter class for syntax highlighting in C and C++ files.
- Developed TerminalWidget for command execution and output display.
- Created TextEditor with line numbering and auto-indentation features.
- Established main application entry point in main.cpp.
- Designed UI layout for MainWindow using Qt Designer.

include/SyntaxHighlighter.h

@@ -0,0 +1,47 @@
+#pragma once
+
+#include <QtGui/QSyntaxHighlighter>
+#include <QtGui/QTextDocument>
+#include <QtGui/QTextCharFormat>
+#include <QtCore/QRegularExpression>
+
+class SyntaxHighlighter : public QSyntaxHighlighter
+{
+    Q_OBJECT
+
+public:
+    explicit SyntaxHighlighter(QTextDocument *parent = nullptr);
+    ~SyntaxHighlighter();
+
+    void setLanguage(const QString &language);
+    QString language() const;
+
+protected:
+    void highlightBlock(const QString &text) override;
+
+private:
+    struct HighlightingRule
+    {
+        QRegularExpression pattern;
+        QTextCharFormat format;
+    };
+    QVector<HighlightingRule> m_highlightingRules;
+
+    void setupCppHighlighting();
+    void setupCHighlighting();
+    void setupCommonRules();
+    
+    QTextCharFormat m_keywordFormat;
+    QTextCharFormat m_classFormat;
+    QTextCharFormat m_singleLineCommentFormat;
+    QTextCharFormat m_multiLineCommentFormat;
+    QTextCharFormat m_quotationFormat;
+    QTextCharFormat m_functionFormat;
+    QTextCharFormat m_numberFormat;
+    QTextCharFormat m_preprocessorFormat;
+
+    QRegularExpression m_commentStartExpression;
+    QRegularExpression m_commentEndExpression;
+    
+    QString m_language;
+};