Update filib

[zfergus]

Description

Update filib and ensure it is linked as a shared library to avoid licensing IPC Toolkit under LGPL

Filib is still completely optional and can be disabled entirely.

Type of change

• Enhancement (non-breaking change which improves existing functionality)

Checklist:

• I have followed the project style guide
• My code follows the clang-format style guidelines of this project
• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 96.31%. Comparing base (ba24d37) to head (a8ed8ef).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #122      +/-   ##
==========================================
+ Coverage   96.30%   96.31%   +0.01%     
==========================================
  Files         102      102              
  Lines        7601     7601              
==========================================
+ Hits         7320     7321       +1     
+ Misses        281      280       -1     

Flag	Coverage Δ
unittests	96.31% <100.00%> (+0.01%)	⬆️

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