Replaced Cell types with Arc/RwLock to make interior mutability thread safe

[marvin-hansen]

…d safe.

Replaced Cell types with Arc/RwLock to make interior mutability thread safe for usage in Tokio runtime.

Describe your changes

Issue ticket number and link

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• All tests are passing when running make test?
• No errors or security vulnerabilities are reported by make check?

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[codecov]

Codecov Report

Attention: 10 lines in your changes are missing coverage. Please review.

Comparison is base (12db26c) 87.85% compared to head (c9f5160) 87.77%.
Report is 3 commits behind head on main.

Files	Patch %	Lines
...ty/src/types/reasoning_types/causaloid/causable.rs	55.00%	9 Missing ⚠️
...ity/src/types/reasoning_types/causaloid/getters.rs	80.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #129      +/-   ##
==========================================
- Coverage   87.85%   87.77%   -0.08%     
==========================================
  Files         123      123              
  Lines        3235     3223      -12     
==========================================
- Hits         2842     2829      -13     
- Misses        393      394       +1     

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