Update meeting notes + contact info (SDR side)

Employee-side meeting edit — notes + client-contact fields only.

Mirrors UpdateMyMeetingRequest in self_service_router exactly, which in turn is bounded by the SdrMeeting ORM columns (shared/infrustructure/db/cdp/models/sdr_meeting.py): only notes, client_contact_name and client_contact_email exist. The field names here are the raw column names because the update is applied via update(SdrMeeting).values(**updates) with no whitelist/rename step — an unknown key (the old contact_name/contact_phone/contact_title /contact_company/contact_linkedin_url set) raises SQLAlchemy "Unconsumed column names" inside the handler and 500s. Lifecycle fields (status, meeting_date, meeting_type, hiring_id) are intentionally not editable — those are calendar-driven client-side fields.