Search for sessions

Autocomplete search over the project's sessions. Returns at most 50 matches, each containing only id, email, userId, name, companyId, companyName and phone. Query parameters: searchTerm (required; terms shorter than 3 characters return an empty array) and fieldExists (optional; only return sessions where that field is set; allowed values: email, userId, phone, companyId, name, companyName, tags, plan, value, sla, lang, avatar, facebookId, instagramId, instagramUsername, telegramChatId, telegramUsername; other values are ignored). Optional scoping: contactViewId limits results to the sessions matching that saved contact view (its conditions apply exactly as in the list route; type/withFeedback are ignored alongside it); without it, type (users | guests | unsubscribed), withFeedback=true and companyId narrow the search like the list route. fullContact=true returns full session documents (without the kv blobs) instead of the 7 autocomplete fields.