perf: Optimize async iterator to eliminate the need for await

[chyroc]

• Improved async iterator to function without requiring await

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 98.81%. Comparing base (4e5547e) to head (2ef5ddd).
Report is 1 commits behind head on main.

@@            Coverage Diff             @@
##             main      #65      +/-   ##
==========================================
+ Coverage   98.76%   98.81%   +0.05%     
==========================================
  Files          38       38              
  Lines        2343     2364      +21     
==========================================
+ Hits         2314     2336      +22     
+ Misses         29       28       -1     

Files with missing lines	Coverage Δ
cozepy/chat/__init__.py	100.00% <100.00%> (ø)
cozepy/model.py	100.00% <100.00%> (ø)
cozepy/workflows/runs/__init__.py	100.00% <100.00%> (ø)
tests/test_chat.py	100.00% <100.00%> (ø)
tests/test_workflow.py	100.00% <100.00%> (ø)

... and 1 file with indirect coverage changes