Module logging 

Server logging: a per-instance, size-bounded, owner-only file log — never stdout (spec §5). stdout is the MCP JSON-RPC channel; any byte there corrupts the protocol. The 128-bit connection token is NEVER passed to a log macro anywhere in the server (enforced by review, not code).

Functions

init_file_logging

Initialize file-only tracing. Returns a guard that MUST be held for the process lifetime (dropping it flushes+stops the writer). log_path is the per-instance path from paths::instance_log_path().