refactor: rename Batch to Partition and update related types and channels for consistency

internal/app/etl/transformers/mssql.go

@@ -64,7 +64,7 @@ const processChunkCtxCheck = 4096
 
 func (mssqlTr *MssqlTransformer) ProcessChunk(
 	ctx context.Context,
-	chunk *models.Chunk,
+	chunk *models.Batch,
 	transformationPlan []etl.ColumnTransformPlan,
 ) error {
 	for i, rowValues := range chunk.Data {
@@ -94,8 +94,8 @@ func (mssqlTr *MssqlTransformer) ProcessChunk(
 func (mssqlTr *MssqlTransformer) Exec(
 	ctx context.Context,
 	columns []models.ColumnType,
-	chChunksIn <-chan models.Chunk,
-	chChunksOut chan<- models.Chunk,
+	chChunksIn <-chan models.Batch,
+	chChunksOut chan<- models.Batch,
 	chJobErrorsOut chan<- custom_errors.JobError,
 	wgActiveChunks *sync.WaitGroup,
 ) {