perf(sdk): Use Django URL resolution for view-based trace sampling

[vgrozdanic]

Summary

Alternative to #115874. Instead of maintaining a parallel list of compiled regexes that duplicate URL patterns from urls.py, this uses Django's resolve() to match the request path against the existing URL conf and then looks up the resolved URL name in a SAMPLED_VIEWS dict.

• O(1) dict lookup instead of linear regex scan
• No regex duplication — sampling config references URL names defined in urls.py, so they can't drift out of sync
• Same fallthrough behavior — exact-match SAMPLED_ROUTES is checked first, then SAMPLED_VIEWS via resolve, then the rest of the sampler logic

Samples AI Conversations endpoints at 100% for rollout monitoring.

Routes covered

SAMPLED_VIEWS: dict[str, float] = {
    "sentry-api-0-organization-ai-conversations": 1.0,
    "sentry-api-0-organization-ai-conversation-details": 1.0,
}