Reorganize structures to reduce memory footprint & Fix disconnect logic issue

[treavorj]

Initially I was going to add an extension feature, but I am fairly certain that I can do what I want to with the existing tools - which is awesome. Prior to doing that though, I did mess around with the structures some and realized that the memory footprint of them could be reduced just by reorganizing them.
No structural changes were made.

clientHandler: 336 bytes -> 320 bytes
Settings: 136 bytes -> 120 bytes
TestServerDriver: 104 bytes -> 096 bytes (I ended up aligning this one after I realized it was a test struct but oh well guess the test is just ever so slightly less memory on the CPU)

[treavorj]

Since my previous PR didn't really do much I went ahead and added a fix to correct a double call that was occurring to the connection disconnect. Should resolve #489.

[codecov]

Codecov Report

❌ Patch coverage is 70.00000% with 9 lines in your changes missing coverage. Please review.
✅ Project coverage is 86.59%. Comparing base (f1742bb) to head (6cd6e9b).
⚠️ Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
client_handler.go	70.00%	6 Missing and 3 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #557      +/-   ##
==========================================
- Coverage   86.80%   86.59%   -0.21%     
==========================================
  Files          12       12              
  Lines        2350     2358       +8     
==========================================
+ Hits         2040     2042       +2     
- Misses        235      241       +6     
  Partials       75       75              

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[fclairamb]

Thank you @treavorj !