fix: import issue for participantsContainer and timestamp

[lyjeileen]

Changes

• Fix importing issue for participantsContainer and timestamp. Participant-related types are moved to the component file because enum couldn't be imported and used directly from the types.ts file. The index file for timestamp was index.tsx instead of index.ts before.

Import path before changes

import { ParticipantRole, ParticipantType } from '@rustic-ai/ui-components/types'

Import path after changes

import { ParticipantRole, ParticipantType } from '@rustic-ai/ui-components/participantsContainer'