Session replay: support v2 trigger groups (conditional recording) #712

Description

Mobile tracker for PostHog/posthog#35661 (Conditional Recording 3000). The replay trigger config is getting a v2 shape, and the mobile SDKs need to support it:

• multiple trigger groups, e.g. (20% sampling + error event) or (linked flag + url)
• minimum duration moving inside a group
• per-SDK matching, e.g. 40% sampling on web and 33% on mobile
• more trigger types on non-web SDKs (event and URL/screen triggers)
• debug properties, so conditional recording can be debugged outside web too

Sibling SDK issues:

• iOS (Session replay: support v2 trigger groups (conditional recording) posthog-ios#775)
• Android (this issue)
• Flutter (Session replay: support v2 trigger groups (conditional recording) posthog-flutter#545)
• RN (Session replay (React Native): support v2 trigger groups (conditional recording) posthog-js#4595)