• feat: add config option to disable swizzling (#388)
• feat: SDK instance now manages its own session (#388)

Note: A potentially breaking change for users with multiple SDK instances. Each SDK instance now manages its own $session_id instead of sharing a global session across all instances.
This aligns with PostHog JS SDK behavior and ensures proper session isolation when using multiple SDK instances.
For single-instance usage (the common case), this change has no impact.