Add WebAssembly (WASM32-wasip1) build target support

[Copilot]

Enables building OpenSSL for WebAssembly using WASI Preview 1, addressing the need to use OpenSSL cryptographic operations in WASM environments.

Changes

Configuration

• Configurations/15-wasm.conf: New platform config defining wasm32-wasip1 and wasm32-wasi targets
  • Compiler: wasm32-wasip1-clang / wasm32-wasi-clang
  • Archiver: llvm-ar, llvm-ranlib
  • Auto-disables: threads, shared libs, asm, dso, engines
  • Bignum ops: BN_LLONG (32-bit with 64-bit long long)

Documentation

• NOTES-WASM.md: Build instructions, prerequisites (WASI SDK), configuration options, troubleshooting
• README.md: Added WASM platform reference

Tooling & Examples

• build-wasm32-wasip1.sh: Automated build script with WASI SDK validation
• demos/wasm/: Working crypto example (SHA-256, AES-256-CBC) with build instructions

Usage

# Option 1: Automated
./build-wasm32-wasip1.sh /path/to/install

# Option 2: Manual
./Configure wasm32-wasip1 --prefix=/path/to/install
make && make install

# Build WASM applications
wasm32-wasip1-clang -O3 \
  -I/path/to/install/include \
  -L/path/to/install/lib \
  -o app.wasm app.c \
  -lssl -lcrypto

Verification

$ ./Configure LIST | grep wasm
wasm32-wasi
wasm32-wasip1

$ ./Configure wasm32-wasip1 --prefix=/tmp/test
Configuring OpenSSL version 4.0.0-dev for target wasm32-wasip1
***   OpenSSL has been successfully configured   ***

Original prompt

how to build openssl 1.0.2a for WASM32-wasip1

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