fix: replace remaining nested double-quote f-strings for Python <3.12 compatibility

tools/legacy/build_plugin_zstd_vs2026.py

@@ -332,7 +332,7 @@ def build_configuration(
     cmd = [
         str(msbuild_path),
         str(project_file),
-        f'/t:{"Rebuild" if rebuild else "Build"}',
+        f'/t:{'Rebuild' if rebuild else 'Build'}',
         f'/p:Configuration={config.config}',
         f'/p:Platform={config.platform}',
         f'/p:OutDir=Build\\{config.name}\\',
@@ -743,14 +743,14 @@ Examples:
             if not success:
                 print(f"  - {config.name}")
 
-    print(f"\n{Colors.BOLD}{Colors.BRIGHT_CYAN}{"-"*50}{Colors.RESET}")
+    print(f"\n{Colors.BOLD}{Colors.BRIGHT_CYAN}{'-'*50}{Colors.RESET}")
     print(f"{Colors.BOLD}{Colors.BRIGHT_CYAN}Build Summary:{Colors.RESET}")
     for config, success, build_time, file_size, dest_path in build_results:
         status = "OK" if success else "FAIL"
         row_color = Colors.BRIGHT_GREEN if success else Colors.RED
         size_str = f"{file_size:,} bytes" if file_size > 0 else "N/A"
         print(f"  {row_color}{status}{Colors.RESET} {config.name:15s} - {format_time(build_time):8s} - {size_str}")
-    print(f"{Colors.BOLD}{Colors.BRIGHT_CYAN}{"-"*50}{Colors.RESET}")
+    print(f"{Colors.BOLD}{Colors.BRIGHT_CYAN}{'-'*50}{Colors.RESET}")
     print(f"Total time: {Colors.BRIGHT_WHITE}{format_time(total_time)}{Colors.RESET}")
     print()