Adjust `mechanism` in `core` SDK

[Lms24]

• errors thrown from event processors: ref(core): Add more specific exception mechanism for internal errors #17253
• supabase ref(core): Improve event mechanism for supabase integration #17286
• openai: ref(core): Add more specific event mechanisms and span origins to openAiIntegration #17288
• trpc: ref(core): Add mechanism.type to trpcMiddleware errors #17287

[linear]

JS-799 Adjust `mechanism` in `core` SDK