Turns out the new cbindgen version generates slightly different
sqlite3.h so commit that to the tree. The version in Cargo.lock also
changed so let's check in that too.
Add enough stubs to be able to link CPython build against Limbo's SQLite
compatibility API:
```
export LIBSQLITE3_LIBS=../limbo/target/debug/liblimbo_sqlite3.a
./configure
make -j8
[snip]
gcc -shared Modules/_sqlite/blob.o Modules/_sqlite/connection.o Modules/_sqlite/cursor.o Modules/_sqlite/microprotocols.o Modules/_sqlite/module.o Modules/_sqlite/prepare_protocol.o Modules/_sqlite/row.o Modules/_sqlite/statement.o Modules/_sqlite/util.o ../limbo/target/debug/liblimbo_sqlite3.a -o Modules/_sqlite3.cpython-314-x86_64-linux-gnu.so
thread '<unnamed>' panicked at sqlite3/src/lib.rs:751:5:
not yet implemented
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
fatal runtime error: failed to initiate panic, error 5
make: *** [Makefile:1511: checksharedmods] Aborted (core dumped)
```
All that's left is to actually implement all of this...
This adds initial SQLite C ABI compatibility to Limbo to make sure we
drive the Rust API in the right way that allows us to implement SQLite
semantics.
