Add GCC-16 to CI

[Copilot]

CI builds began failing while configuring the updated libsodium vcpkg port because required autoreconf tools were absent.

• Linux CI: Add autoconf-archive and automake to sanitizer, system-test, and Codecov setup dependencies.
• macOS CI: Add autoconf-archive to sanitizer setup.
• vcpkg builds: Add autoreconf dependencies to Linux and macOS master/release matrices.

apt-get install ... autoconf autoconf-archive automake
brew install ... automake autoconf autoconf-archive libtool

[codecov]

Codecov Report

❌ Patch coverage is 90.19608% with 5 lines in your changes missing coverage. Please review.
✅ Project coverage is 87.01%. Comparing base (3dd946d) to head (3abc022).

Files with missing lines	Patch %	Lines
test/Main.cpp	25.00%	3 Missing ⚠️
test/integration_tests/TerminalTest.cpp	77.77%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #776      +/-   ##
==========================================
- Coverage   87.03%   87.01%   -0.03%     
==========================================
  Files          72       72              
  Lines        5639     5676      +37     
  Branches      532      533       +1     
==========================================
+ Hits         4908     4939      +31     
- Misses        731      736       +5     
- Partials        0        1       +1     

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