ad34fe88f2
Whole C strings IN are [:0]u8 (the std convention, popen/getenv) with terminated copies built via cstring(); nullable C strings OUT are *u8 with the getenv-style cast null-check — usize said nothing about what crossed the boundary. prepare_v2/bind_text stay [*]u8 + explicit byte length on purpose: those are (ptr, nByte) APIs, which is what lets un-terminated sx string views pass without copying. Handles stay usize so sqlite3_open's out-param is a single-level *usize.