Clear develop Sonar code smells without HTTP/2 send-path changes

[justcoding121]

Summary

• Clears the 52 open SonarCloud code smells on develop.
• Hot-path HTTP/2 DATA queue, deferred drain, and header-block signatures stay as they are (explicit parameters, no per-frame context object, no LINQ on the wire path). Header delimiter checks now use allocation-free IndexOfAny.
• Fixes the two unit tests that looked up instance terminate-lite helpers with static binding flags, which was failing the .NET build before SonarCloud could upload.

Test plan

• dotnet build src/Titanium.Web.Proxy.sln -c Release --warnaserror
• Full Titanium.Web.Proxy.UnitTests (1838 passed)
• Inspector session/archive/UI filter (186 passed)
• .NET workflow, including SonarCloud upload, reports 0 code smells on this branch
• After merge, the develop code-smells badge is 0 and the quality gate stays green

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
88.9% Coverage on New Code
0.7% Duplication on New Code

See analysis details on SonarQube Cloud