Initial mediator work

[nain-F49FF806]

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[codecov-commenter]

Codecov Report

Merging #976 (d07c054) into main (725797b) will decrease coverage by 1.51%.
The diff coverage is n/a.

❗ Current head d07c054 differs from pull request most recent head 2821f11. Consider uploading reports for the commit 2821f11 to get more accurate results

@@            Coverage Diff             @@
##             main     #976      +/-   ##
==========================================
- Coverage   30.39%   28.89%   -1.51%     
==========================================
  Files         422      419       -3     
  Lines       26227    25981     -246     
  Branches     5084     5228     +144     
==========================================
- Hits         7972     7506     -466     
- Misses      16038    16271     +233     
+ Partials     2217     2204      -13     

Flag	Coverage Δ
unittests-aries-vcx	28.89% <ø> (-1.51%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files	Coverage Δ
aries_vcx/src/protocols/connection/generic/mod.rs	9.30% <ø> (+0.14%)	⬆️
aries_vcx/src/protocols/connection/mod.rs	4.54% <ø> (-3.35%)	⬇️

... and 310 files with indirect coverage changes

[nain-F49FF806]

#977 does more on top of these changes. Consider that PR instead.