fix: 修复 Windows arm64 可执行文件图标嵌入构建失败

MSYS2 CLANGARM64 环境下使用 llvm-windres，需使用 LLVM target triple
(aarch64-w64-mingw32) 而非 GNU BFD 格式 (pe-aarch64)。新增双格式变量
并增强 windres 检测逻辑，通过 --version 输出区分 GNU/LLVM 工具。

Makefile

@@ -35,13 +35,15 @@ ifeq ($(TARGET_ARCH),arm64)
 APPIMAGE_ARCH := aarch64
 DEB_ARCH := arm64
 RPM_ARCH := aarch64
-WINDOWS_WINDRES_FORMAT := pe-aarch64
+WINDOWS_WINDRES_FORMAT_BFD := pe-aarch64
+WINDOWS_WINDRES_FORMAT_LLVM := aarch64-w64-mingw32
 WINDOWS_RESOURCE := rsrc_windows_arm64.syso
 else
 APPIMAGE_ARCH := x86_64
 DEB_ARCH := amd64
 RPM_ARCH := x86_64
-WINDOWS_WINDRES_FORMAT := pe-x86-64
+WINDOWS_WINDRES_FORMAT_BFD := pe-x86-64
+WINDOWS_WINDRES_FORMAT_LLVM := x86_64-w64-mingw32
 WINDOWS_RESOURCE := rsrc_windows_amd64.syso
 endif
 
@@ -177,13 +179,16 @@ _desktop-prepare-embedfs:
 
 _desktop-prepare-windows-resource: _check-windows-target-arch
 	@printf 'Preparing Windows $(TARGET_ARCH) executable icon...\n'
-	@if [ "$(TARGET_ARCH)" = "arm64" ] && [ "$(WINDRES)" = "windres" ] && command -v llvm-windres >/dev/null 2>&1; then \
+	@WINDRES_CMD="$(WINDRES)"; \
+	WINDRES_FMT="$(WINDOWS_WINDRES_FORMAT_BFD)"; \
+	if command -v llvm-windres >/dev/null 2>&1; then \
 		WINDRES_CMD=llvm-windres; \
-	else \
-		WINDRES_CMD="$(WINDRES)"; \
+		WINDRES_FMT="$(WINDOWS_WINDRES_FORMAT_LLVM)"; \
+	elif "$$WINDRES_CMD" --version 2>&1 | grep -qi LLVM; then \
+		WINDRES_FMT="$(WINDOWS_WINDRES_FORMAT_LLVM)"; \
 	fi; \
 	command -v "$$WINDRES_CMD" >/dev/null 2>&1 || { printf 'Missing windres tool: %s\n' "$$WINDRES_CMD"; exit 1; }; \
-	cd backend/cmd/desktop && "$$WINDRES_CMD" -O coff -F $(WINDOWS_WINDRES_FORMAT) -i icon_windows.rc -o $(WINDOWS_RESOURCE)
+	cd backend/cmd/desktop && "$$WINDRES_CMD" -O coff -F "$$WINDRES_FMT" -i icon_windows.rc -o $(WINDOWS_RESOURCE)
 
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