chore: Handle conversation participation creation race condition error

[sojan-official]

We observed some race condition errors in the conversation participation listener while trying to create a conversation participation assignment. This PR handles this error and also adds additional debug information for future

fixes: https://linear.app/chatwoot/issue/CW-3296/activerecordrecordnotunique-pguniqueviolation-error-duplicate-key

Changelog

• handles ActiveRecord::RecordNotUnique, ActiveRecord::RecordInvald errors so that they won't pollute sentry
• Adds a debug statement to log the cases
• Add previous_changes into the dispatcher so that we know the exact attribute changes which trigger assignee_changed, team_changed events ( would be handy in future )

[linear]

CW-3296 ActiveRecord::RecordNotUnique: PG::UniqueViolation: ERROR: duplicate key value violates unique constraint "index_conversation_p...