Prepare a Sentry dogfooding branch

[sentrivana]

Prepare a branch for migrating Sentry to span streaming.

There's a skill that can be used: getsentry/sentry-for-ai#156 (updates to the skill in case of overlooked/incorrect stuff very welcome!)

Additionally to the usual migration patterns (set_data -> set_attribute, set_op -> set_attribute("sentry.op", …), etc.), would be good to add the following:

• if there's a tag set on the scope, keep and add an equivalent scope.set_attribute so that it also gets applied to spans

[linear-code]

PY-2522