DesktopAgent backend implementation

[ZKRobi]

No description provided.

[codecov]

Codecov Report

Merging #233 (adb51e9) into main (a5afc1d) will decrease coverage by 0.09%.
The diff coverage is 76.56%.

❗ Current head adb51e9 differs from pull request most recent head f3c79e6. Consider uploading reports for the commit f3c79e6 to get more accurate results

@@            Coverage Diff             @@
##             main     #233      +/-   ##
==========================================
- Coverage   72.94%   72.86%   -0.09%     
==========================================
  Files         139      147       +8     
  Lines        4628     4887     +259     
  Branches      139      139              
==========================================
+ Hits         3376     3561     +185     
- Misses       1251     1325      +74     
  Partials        1        1              

Impacted Files	Coverage Δ
src/shell/dotnet/Shell/App.xaml.cs	0.00% <0.00%> (ø)
.../DesktopAgent/src/DesktopAgent/Fdc3DesktopAgent.cs	51.72% <51.72%> (ø)
.../src/DesktopAgent/Contracts/FindChannelResponse.cs	75.00% <75.00%> (ø)
...otnet/DesktopAgent/src/DesktopAgent/UserChannel.cs	84.05% <84.05%> (ø)
.../dotnet/DesktopAgent/src/DesktopAgent/Fdc3Topic.cs	90.90% <90.90%> (ø)
...t/src/DesktopAgent/Contracts/FindChannelRequest.cs	100.00% <100.00%> (ø)
...DesktopAgent/Contracts/GetCurrentContextRequest.cs	100.00% <100.00%> (ø)
...gent/DependencyInjection/Fdc3DesktopAgentConfig.cs	100.00% <100.00%> (ø)
...DependencyInjection/ServiceCollectionExtensions.cs	100.00% <100.00%> (ø)

... and 12 files with indirect coverage changes