Extend fuel-core for the watchtower (#2372)

This PR extends the `fuel-core` too make public some functionality that
could be useful to reuse in the watchtower
https://github.com/FuelLabs/network-watchtower.

### Before requesting review
- [x] I have reviewed the code myself

crates/compression/src/lib.rs

@@ -16,6 +16,7 @@ pub use registry::RegistryKeyspace;
 use fuel_core_types::{
     blockchain::header::PartialBlockHeader,
     fuel_tx::CompressedTransaction,
+    fuel_types::BlockHeight,
 };
 use registry::RegistrationsPerTable;
 
@@ -42,6 +43,15 @@ impl Default for VersionedCompressedBlock {
     }
 }
 
+impl VersionedCompressedBlock {
+    /// Returns the height of the compressed block.
+    pub fn height(&self) -> &BlockHeight {
+        match self {
+            VersionedCompressedBlock::V0(block) => block.header.height(),
+        }
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use fuel_core_compression as _;

crates/compression/src/registry.rs

@@ -78,7 +78,7 @@ macro_rules! tables {
 
 
         impl RegistrationsPerTable {
-            pub(crate) fn write_to_registry<R>(&self, registry: &mut R, timestamp: Tai64) -> anyhow::Result<()>
+            pub fn write_to_registry<R>(&self, registry: &mut R, timestamp: Tai64) -> anyhow::Result<()>
             where
                 R: TemporalRegistryAll
             {

crates/fuel-core/src/database.rs

@@ -408,7 +408,7 @@ impl Modifiable for GenesisDatabase<Relayer> {
     }
 }
 
-fn commit_changes_with_height_update<Description>(
+pub fn commit_changes_with_height_update<Description>(
     database: &mut Database<Description>,
     changes: Changes,
     heights_lookup: impl Fn(

crates/fuel-core/src/state/generic_database.rs

@@ -44,7 +44,7 @@ impl<Storage> GenericDatabase<Storage> {
     }
 
     pub fn into_inner(self) -> Storage {
-        self.storage.into_inner()
+        self.storage.into_storage()
     }
 }
 

crates/storage/src/structured_storage.rs

@@ -105,7 +105,7 @@ impl<S> StructuredStorage<S> {
     }
 
     /// Returns the inner storage.
-    pub fn into_inner(self) -> S {
+    pub fn into_storage(self) -> S {
         self.inner
     }
 }

crates/storage/src/transactional.rs

@@ -112,6 +112,13 @@ impl<S> StorageTransaction<S> {
         self.inner.changes
     }
 
+    /// Returns the storage and changes to it.
+    pub fn into_inner(self) -> (S, Changes) {
+        let storage = self.inner.storage;
+        let changes = self.inner.changes;
+        (storage, changes)
+    }
+
     /// Resets the changes to the storage.
     pub fn reset_changes(&mut self) {
         self.inner.changes = Default::default();
@@ -259,10 +266,7 @@ pub trait WriteTransaction {
     fn write_transaction(&mut self) -> StorageTransaction<&mut Self>;
 }
 
-impl<S> WriteTransaction for S
-where
-    S: Modifiable,
-{
+impl<S> WriteTransaction for S {
     fn write_transaction(&mut self) -> StorageTransaction<&mut Self> {
         StorageTransaction::transaction(
             self,