Include flatc encryption module in npm package

Use WASM wallet runtime in flatc package

Fix emsdk workflow env resolution

Use latest Node in WASM workflows

FlatBuffers release v25.12.19-da.2

Publish npm artifacts for 25.12.19/25.12.19-wasm.62

Fix Mac universal build: build OpenSSL for each arch and lipo

openssl-cmake only supports one architecture at a time. For universal
builds (arm64+x86_64), download OpenSSL source directly, configure for
each architecture separately, build via custom commands, and lipo the
resulting static libraries into universal binaries.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Build OpenSSL from source via FetchContent for FIPS compliance

Replace find_package(OpenSSL) with jimmy-park/openssl-cmake FetchContent
build so OpenSSL is always compiled from source rather than relying on
system packages. This ensures FIPS compliance and fixes Mac universal
builds which previously had to disable OpenSSL entirely.

- CMakeLists.txt: FetchContent with enable-fips, MSVC static RT, SYSTEM includes
- build.yml: Remove Mac universal OpenSSL disable; add Perl+NASM on Windows CI
- BuildWasm.cmake: Replace nicedoc/openssl-wasm with jimmy-park/openssl-cmake

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Fix remaining CI failures: MSVC CRT mismatch, static OpenSSL, Mac uni…

…versal

- Set CMAKE_MSVC_RUNTIME_LIBRARY globally to /MT for consistent SEAL linkage
- Make OpenSSL gracefully optional (QUIET find, disable if not found)
- Prefer static OpenSSL when FLATBUFFERS_STATIC_FLATC is on
- Replace -static with -static-libgcc -static-libstdc++ for Linux
- Disable OpenSSL for Mac universal builds (Homebrew is native-arch only)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Fix CI build failures: SEAL API compatibility and warning cleanup

- Fix SEAL 4.1 KeyGenerator API: InitClientSeeded falls back to random
  key generation since SEAL 4.1 doesn't accept PRNG in constructor
- Fix unused parameter warnings in encryption.cpp (pub_size,
  private_key_size)
- Add static to test functions in he_encryption_test.cpp to fix
  -Werror=missing-declarations
- Mark SEAL headers as SYSTEM includes in CMake to suppress
  third-party -Wextra-semi warnings
- Add pragma guards around SEAL include for GCC/Clang portability

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>