feat: add cython typing for ServiceInterface.name

[bdraco]

We compare this a lot so we want to force __Pyx_PyUnicode_Equals

[codecov]

Codecov Report

Patch coverage: 50.00% and project coverage change: -0.22% ⚠️

Comparison is base (8f39ba3) 83.60% compared to head (975dcd6) 83.38%.
Report is 2 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #248      +/-   ##
==========================================
- Coverage   83.60%   83.38%   -0.22%     
==========================================
  Files          28       28              
  Lines        3263     3263              
  Branches      677      677              
==========================================
- Hits         2728     2721       -7     
- Misses        324      328       +4     
- Partials      211      214       +3     

Files Changed	Coverage Δ
src/dbus_fast/__version__.py	0.00% <0.00%> (ø)
src/dbus_fast/service.py	87.97% <100.00%> (ø)

... and 2 files with indirect coverage changes

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.