fix: add thread safety for pinyin dictionary initialization

Add mutex protection to prevent race condition in multi-threaded access
to the static pinyin dictionary. The `InitDict()` function was not
thread-safe when called concurrently from multiple threads, which could
lead to double initialization or data corruption.

1. Add `QMutex` and `QMutexLocker` includes
2. Declare static `dictMutex` to protect the dictionary
3. Lock mutex at the beginning of `InitDict()` to ensure exclusive
access
4. Prevent potential crash when multiple threads simultaneously trigger
dictionary loading

Influence:
1. Test concurrent pinyin conversion from multiple threads
2. Verify no crash occurs during high-frequency multi-threaded access
3. Test dictionary initialization under thread contention
4. Verify performance impact of mutex locking in single-threaded
scenarios
5. Test edge cases where InitDict is called simultaneously from
different threads

fix: 添加拼音字典初始化的线程安全保护

添加互斥锁保护以防止多线程访问静态拼音字典时的竞态条件。`InitDict()` 函
数在被多线程并发调用时不是线程安全的，可能导致重复初始化或数据损坏。

1. 添加 `QMutex` 和 `QMutexLocker` 头文件包含
2. 声明静态 `dictMutex` 用于保护字典
3. 在 `InitDict()` 开头加锁以确保独占访问
4. 防止多线程同时触发字典加载时可能导致的崩溃

Influence:
1. 测试多线程并发进行拼音转换的场景
2. 验证高频多线程访问时无崩溃发生
3. 测试线程竞争条件下的字典初始化
4. 验证单线程场景下互斥锁锁定的性能影响
5. 测试不同线程同时调用 InitDict 的边界情况

Author: caixr23

src/util/dpinyin.cpp

@@ -1,4 +1,4 @@
-// SPDX-FileCopyrightText: 2019 - 2023 UnionTech Software Technology Co., Ltd.
+// SPDX-FileCopyrightText: 2019 - 2026 UnionTech Software Technology Co., Ltd.
 //
 // SPDX-License-Identifier: LGPL-3.0-or-later
 
@@ -8,18 +8,27 @@
 #include <QSet>
 #include <QTextStream>
 #include <QMap>
+#include <QMutex>
+#include <QMutexLocker>
 #include <QDebug>
 
 DCORE_BEGIN_NAMESPACE
 
 static QHash<uint, QString> dict = {};
+static QMutex dictMutex;
 const char kDictFile[] = ":/dpinyin/resources/dpinyin.dict";
 
 static void InitDict() {
     if (!dict.isEmpty()) {
         return;
     }
 
+    QMutexLocker locker(&dictMutex);
+
+    if (!dict.isEmpty()) {
+        return;
+    }
+
     dict.reserve(25333);
 
     QFile file(kDictFile);