[Omi] Conversation titles should show actual user name

## Problem Conversation titles/summaries use generic "user" or "Speaker 0" instead of the user's actual name, even though the system knows it. **Example:** - Current: "User discussing project with John" - Expected: "Aarav discussing project with John" ## Root Cause The conversation structuring prompt in `backend/utils/llm/conversation_processing.py` (line ~651) doesn't include the user's name. It only uses calendar meeting participant names when available. ## Fix **File:** `backend/utils/llm/conversation_processing.py` **Function:** `get_transcript_structure()` (line ~631) ### 1. Add `uid` parameter ```python def get_transcript_structure( transcript: str, started_at: datetime, language_code: str, tz: str, uid: str, # ADD THIS photos: List[ConversationPhoto] = None, calendar_meeting_context: 'CalendarMeetingContext' = None, ) -> Structured: ``` ### 2. Get user name at start of function ```python from database.auth import get_user_name def get_transcr