FFI and Julia Bindings for incremental scan changes (#6)

FFI and Julia Bindings for incremental scan changes that were introduced
with RelationalAI/iceberg-rust#3.

I refactored the file structures a bit, for both Rust and Julia code.
Rust code reuses some common parts through macros, for Julia I didn't
bother to do that (mostly afraid of macros and ccall interaction being a
rabbit hole with little benefit).
Note that I had to use struct instead of const for `ScanRef`, since now
with additional type, we have method overloads, which if we use
`ScanRef` const aliases actually use same type, and then become
overwrites instead of overloads.

There's also a new test data, and new test that exercises positional
delete and inserts.

---------

Co-authored-by: Gerald Berger <[email protected]>

Author: vustef

.github/workflows/test.yml

@@ -61,10 +61,13 @@ jobs:
               -e MINIO_ROOT_USER=root \
               -e MINIO_ROOT_PASSWORD=password \
               -e MINIO_DOMAIN=minio \
-              -v ${{ github.workspace }}/assets/tpch:/input minio/minio:latest server /data/
+              -v ${{ github.workspace }}/assets/tpch:/input \
+              -v ${{ github.workspace }}/assets/incremental:/input_incremental \
+              minio/minio:latest server /data/
             until (docker exec minio mc alias set minio http://localhost:9000 root password) do echo '... waiting ...' && sleep 1; done;
             docker exec minio mc mb minio/warehouse
             docker exec minio mc cp -r /input/tpch.sf01/ minio/warehouse/tpch.sf01/
+            docker exec minio mc cp -r /input_incremental/ minio/warehouse/incremental/;
             docker run -d --name rest \
               --network=iceberg_net \
               -p 8181:8181 \

.gitignore

@@ -1,5 +1,7 @@
 **/.env
 iceberg_rust_ffi/target
+iceberg_rust_ffi/target/**/*
 iceberg_rust_ffi/integration_test
 **/*.dylib
-**/.claude
+**/.claude
+**/.DS_Store

CLAUDE.md

@@ -48,7 +48,7 @@ test: build
 		exit 1; \
 	fi
 	@set -a && . ./.env && set +a && \
-		export ICEBERG_RUST_LIB=$(TARGET_DIR) && \
+		export ICEBERG_RUST_LIB=$$(pwd)/$(TARGET_DIR) && \
 		$(JULIA_THREADS_ENV) julia --project=. -e 'using Pkg; Pkg.test()'
 
 # Start Julia REPL with environment configured (requires .env file)
@@ -58,7 +58,7 @@ repl: build
 		exit 1; \
 	fi
 	@set -a && . ./.env && set +a && \
-		export ICEBERG_RUST_LIB=$(TARGET_DIR) && \
+		export ICEBERG_RUST_LIB=$$(pwd)/$(TARGET_DIR) && \
 		$(JULIA_THREADS_ENV) julia --project=.
 
 # Clean build artifacts