lmcp-api#11 phase 0: /mcp requests per UTC day by one dimension.

protocol_version: every valid request by the version it declares (none = declared none, which is also every post-handshake request of a 2024-11-05/2025-03-26 client; other-date = a date that is no MCP revision; other = not a date). initialize_protocol_version: the handshakes by the version asked for — the number a cutoff decision needs. public_host (lmcp-api#76): apex | www | direct (reached this API without the web front); www_client: the client family of the www requests; www_auth: token | none for www requests (what a redirect would break is an authenticated www connector). The tag can be forged by calling the origin directly: read it as a decision aid. Today's row lags by up to a minute per process (counts are persisted once a minute).