Add NSIS plugin support and extraction functionality

- Implemented plugin API in `pluginapi.cpp` and `pluginapi.h` for NSIS integration.
- Added resource files `resource.h` and `resource.rc` for versioning and resource management.
- Created `ExtractCallbackConsole` class to handle extraction progress and user input.
- Developed main extraction logic in `Main.cpp` and `MainAr.cpp` for handling archives.
- Introduced user input utilities in `UserInputUtils2.cpp` and `UserInputUtils2.h` for password handling and user prompts.
- Added break signal handling in `NSISBreak.cpp` and `NSISBreak.h` for graceful interruption of extraction processes.
- Included standard header `StdAfx.h` for precompiled headers and common includes.

tools/fix_vcxproj.py

@@ -0,0 +1,37 @@
+#!/usr/bin/env python3
+"""Add missing source files to Nsis7z_vs2026.vcxproj"""
+from pathlib import Path
+
+ROOT = Path(__file__).resolve().parent.parent
+vcxproj = ROOT / 'versions/zstd/CPP/7zip/Bundles/Nsis7z/Nsis7z_vs2026.vcxproj'
+
+# Relative paths from vcxproj dir (versions/zstd/CPP/7zip/Bundles/Nsis7z/)
+# 5 levels up = versions/
+MISSING = [
+    r'..\..\..\..\..\7-zip-zstd\CPP\Common\MyWindows.cpp',
+    r'..\..\..\..\..\7-zip-zstd\C\hashes\xxhash.c',
+    r'..\..\..\..\..\7-zip-zstd\C\fast-lzma2\dict_buffer.c',
+    r'..\..\..\..\..\7-zip-zstd\C\fast-lzma2\fl2_common.c',
+    r'..\..\..\..\..\7-zip-zstd\C\fast-lzma2\fl2_compress.c',
+    r'..\..\..\..\..\7-zip-zstd\C\fast-lzma2\fl2_pool.c',
+    r'..\..\..\..\..\7-zip-zstd\C\fast-lzma2\fl2_threading.c',
+    r'..\..\..\..\..\7-zip-zstd\C\fast-lzma2\lzma2_enc.c',
+    r'..\..\..\..\..\7-zip-zstd\C\fast-lzma2\radix_bitpack.c',
+    r'..\..\..\..\..\7-zip-zstd\C\fast-lzma2\radix_mf.c',
+    r'..\..\..\..\..\7-zip-zstd\C\fast-lzma2\radix_struct.c',
+    r'..\..\..\..\..\7-zip-zstd\C\fast-lzma2\range_enc.c',
+    r'..\..\..\..\..\7-zip-zstd\C\fast-lzma2\util.c',
+]
+
+content = vcxproj.read_text(encoding='utf-8')
+
+ANCHOR = '    <ClCompile Include="..\\..\\UI\\NSIS\\ExtractCallbackConsole.cpp" />'
+if ANCHOR not in content:
+    print('ERROR: anchor not found in vcxproj')
+    exit(1)
+
+lines = [f'    <ClCompile Include="{p}" />' for p in MISSING]
+block = '\n'.join(lines) + '\n    '
+content = content.replace(ANCHOR, block + ANCHOR.lstrip())
+vcxproj.write_text(content, encoding='utf-8')
+print(f'Added {len(MISSING)} source files to vcxproj')