Don't call ICU's u_init/u_shutdown

Doing so is not necessary with modern ICU versions and because we use
system-provided ICU, u_cleanup() can (and does, on macOS 26) lead to
crashes during shutdown.

See https://unicode-org.github.io/icu/userguide/icu4c/

Author: vslavik

src/edapp.cpp

@@ -532,8 +532,6 @@ int PoeditApp::OnExit()
 
     dispatch::cleanup();
 
-    u_cleanup();
-
     return wxApp::OnExit();
 }
 

src/quicklook/GeneratePreviewForURL.cpp

@@ -81,9 +81,6 @@ extern "C"
 
 void Initialize_plugin(void)
 {
-    UErrorCode err = U_ZERO_ERROR;
-    u_init(&err);
-
     wxInitialize();
 
     CFBundleRef bundle = CFBundleGetBundleWithIdentifier(CFSTR("net.poedit.PoeditQuicklook"));
@@ -101,6 +98,8 @@ void Initialize_plugin(void)
 
             wxString bestTrans = trans->GetBestTranslation("poedit-quicklook");
             Language uiLang = Language::TryParse(bestTrans.ToStdWstring());
+
+            UErrorCode err = U_ZERO_ERROR;
             uloc_setDefault(uiLang.IcuLocaleName().c_str(), &err);
         }
         CFRelease(url);
@@ -110,7 +109,6 @@ void Initialize_plugin(void)
 void Uninitialize_plugin(void)
 {
     wxUninitialize();
-    u_cleanup();
 }
 
 

src/quicklook/PreviewProvider.mm

@@ -51,9 +51,6 @@
 
 void initialize_extension()
 {
-    UErrorCode err = U_ZERO_ERROR;
-    u_init(&err);
-
     wxInitialize();
 
     auto resources = str::to_wx(NSBundle.mainBundle.resourcePath);
@@ -65,13 +62,14 @@ void initialize_extension()
 
     wxString bestTrans = trans->GetBestTranslation("poedit-quicklook");
     Language uiLang = Language::TryParse(bestTrans.ToStdWstring());
+
+    UErrorCode err = U_ZERO_ERROR;
     uloc_setDefault(uiLang.IcuLocaleName().c_str(), &err);
 }
 
 void cleanup_extension()
 {
     wxUninitialize();
-    u_cleanup();
 }
 
 NSData *create_html_preview(const wxString& filename)