sqlite3 command-line interface crashes on a NUL byte or lone surrogate in an input line

Bug description

The python -m sqlite3 interactive shell crashes with a traceback and exits
when an input line contains an embedded NUL byte, or a lone surrogate under a
surrogateescape stdin. sqlite3.complete_statement() raises ValueError
(embedded NUL) or UnicodeEncodeError (lone surrogate); neither is a
sqlite3.Error, so it escapes the REPL instead of being reported like an
ordinary error.

$ printf "SELECT '\0';\nSELECT 1;\n" | python -m sqlite3
sqlite> Traceback (most recent call last):
  ...
ValueError: embedded null character

The following SELECT 1; never runs. Invalid SQL and unknown dot-commands, by
contrast, print a clean error and keep the shell running.

CPython versions tested on

3.14, 3.15, 3.16

Operating systems tested on

macOS

Linked PRs

• gh-153732

Start by running the reported inputs through the python -m sqlite3 interactive shell and inspect how it calls sqlite3.complete_statement(). Done means NUL-byte and lone-surrogate input produce a clean error, while the shell remains running and processes the following statement.