fix(en): make interop_roots optional (#4345)

## What ❔

make interop_roots optional

## Why ❔

back compatibility (en v29 works with main node v28)

## Is this a breaking change?
- [ ] Yes
- [x] No

## Operational changes
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## Checklist

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lint`.

Author: perekopskiy

core/lib/dal/src/models/storage_sync.rs

@@ -130,7 +130,7 @@ impl SyncBlock {
             protocol_version: self.protocol_version,
             pubdata_params: Some(self.pubdata_params),
             pubdata_limit: self.pubdata_limit,
-            interop_roots: self.interop_roots,
+            interop_roots: Some(self.interop_roots),
         }
     }
 

core/lib/types/src/api/en.rs

@@ -48,7 +48,7 @@ pub struct SyncBlock {
     /// Pubdata limit for the batch.
     pub pubdata_limit: Option<u64>,
     /// Interop roots for this block
-    pub interop_roots: Vec<InteropRoot>,
+    pub interop_roots: Option<Vec<InteropRoot>>,
 }
 
 /// Global configuration of the consensus served by the main node to the external nodes.

core/node/node_sync/src/fetcher.rs

@@ -109,7 +109,7 @@ impl TryFrom<SyncBlock> for FetchedBlock {
                 .collect(),
             pubdata_params,
             pubdata_limit: block.pubdata_limit,
-            interop_roots: block.interop_roots.clone(),
+            interop_roots: block.interop_roots.clone().unwrap_or_default(),
         })
     }
 }

core/node/node_sync/src/tests.rs

@@ -69,7 +69,7 @@ impl MockMainNodeClient {
             protocol_version: ProtocolVersionId::latest(),
             pubdata_params: Default::default(),
             pubdata_limit: Some(100_000),
-            interop_roots: vec![],
+            interop_roots: Some(vec![]),
         };
 
         Self {