List Conversations

List conversations for the current client.

A conversation = one lead with at least one INBOUND message. Sorted by last-message timestamp, newest first.

A6 unread semantics:

• unread_total is GLOBAL (all conversations, not just this page).
• unread_only=true filters in SQL BEFORE pagination — pages can no longer come back empty while unread conversations exist deeper.
• total = all conversations normally; = unread conversations when unread_only is set. Implementation: one query pulls every inbound (lead_id, created_at) for the client, and the per-lead cursor comparison happens in Python. Exact, single round-trip, and fine at pilot scale (inbound volume is small); at ~thousands of inbound rows move the cursor map to a real table and do the anti-join in SQL (see plan A6 "real fix").