Checking do_not_track_routes after start session

You call `session_start()` that sends `Cache-control: no-cache` headers before checking `do_not_track_routes.` So it is inpossible to set http cache.

Locate the route handling that calls session_start() and checks do_not_track_routes, then inspect the order in which those operations occur. The change is complete when excluded routes can preserve HTTP caching without session_start() sending no-cache headers first; verify the behavior with a focused regression test if the project’s test structure supports it.

Written by the indexing model from the issue text.