refactor(tvix/castore): move *Node and Directory to crate root

*Node and Directory are types of the tvix-castore model, not the tvix
DirectoryService model. A DirectoryService only happens to send
Directories.

Move types into individual files in a nodes/ subdirectory, as it's
gotten too cluttered in a single file, and (re-)export all types from
the crate root.

This has the effect that we now cannot poke at private fields directly
from other files inside `crate::directoryservice` (as it's not all in
the same file anymore), but that's a good thing, it now forces us to go
through the proper accessors.

For the same reasons, we currently also need to introduce the `rename`
functions on each *Node directly.

A followup is gonna move the names out of the individual enum kinds, so
we can better represent "unnamed nodes".

Change-Id: Icdb34dcfe454c41c94f2396e8e99973d27db8418
Reviewed-on: https://cl.tvl.fyi/c/depot/+/12199
Reviewed-by: yuka <yuka@yuka.dev>
Autosubmit: flokli <flokli@flokli.de>
Tested-by: BuildkiteCI

tvix/store/src/nar/import.rs

@@ -7,12 +7,12 @@ use tokio::{
 };
 use tvix_castore::{
     blobservice::BlobService,
-    directoryservice::{DirectoryService, NamedNode, Node},
+    directoryservice::DirectoryService,
     import::{
         blobs::{self, ConcurrentBlobUploader},
         ingest_entries, IngestionEntry, IngestionError,
     },
-    PathBuf,
+    PathBuf, {NamedNode, Node},
 };
 
 /// Ingests the contents from a [AsyncRead] providing NAR into the tvix store,
@@ -171,13 +171,12 @@ mod test {
     use rstest::*;
     use tokio_stream::StreamExt;
     use tvix_castore::blobservice::BlobService;
-    use tvix_castore::directoryservice::{
-        Directory, DirectoryNode, DirectoryService, FileNode, Node, SymlinkNode,
-    };
+    use tvix_castore::directoryservice::DirectoryService;
     use tvix_castore::fixtures::{
         DIRECTORY_COMPLICATED, DIRECTORY_WITH_KEEP, EMPTY_BLOB_DIGEST, HELLOWORLD_BLOB_CONTENTS,
         HELLOWORLD_BLOB_DIGEST,
     };
+    use tvix_castore::{Directory, DirectoryNode, FileNode, Node, SymlinkNode};
 
     use crate::tests::fixtures::{
         blob_service, directory_service, NAR_CONTENTS_COMPLICATED, NAR_CONTENTS_HELLOWORLD,

tvix/store/src/nar/mod.rs

@@ -8,7 +8,7 @@ pub use import::ingest_nar_and_hash;
 pub use renderer::calculate_size_and_sha256;
 pub use renderer::write_nar;
 pub use renderer::SimpleRenderer;
-use tvix_castore::directoryservice::Node;
+use tvix_castore::Node;
 
 #[async_trait]
 pub trait NarCalculationService: Send + Sync {

tvix/store/src/nar/renderer.rs

@@ -10,7 +10,8 @@ use tracing::{instrument, Span};
 use tracing_indicatif::span_ext::IndicatifSpanExt;
 use tvix_castore::{
     blobservice::BlobService,
-    directoryservice::{DirectoryService, NamedNode, Node},
+    directoryservice::DirectoryService,
+    {NamedNode, Node},
 };
 
 pub struct SimpleRenderer<BS, DS> {