Adding type hints for other End files delegating.py, grouping.py, ipexing.py, notifying.py, exchanging.py

[Sotatek-Patrick-Vu]

[codecov[bot]]

Codecov Report

:x: Patch coverage is 99.43182% with 1 line in your changes missing coverage. Please review. :white_check_mark: Project coverage is 86.89%. Comparing base (1f22907) to head (909308c). :warning: Report is 4 commits behind head on main.

Files with missing lines	Patch %	Lines
src/keria/peer/exchanging.py	88.88%	1 Missing :warning:

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #399      +/-   ##
==========================================
+ Coverage   86.60%   86.89%   +0.29%     
==========================================
  Files          25       25              
  Lines        5286     5442     +156     
==========================================
+ Hits         4578     4729     +151     
- Misses        708      713       +5     

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[kentbull]

Please rebase this and then we can merge it.

[iFergal]

@lenkan I'm going to merge since this has been reviewed by myself and Kent, but feel free to retroactively look at it later in case you spot anything.