Use a separate database for each data domain

[xgreenx]

Closes #1568

The change splits the Database into 3 databases:

• Database<OnChain> - Stores only data required for normal work of the blockchain.
• Database<OffChain> - Stores only data used by the off-chain services like GraphQL.
• Database<Relayer> - Stores relayer-related data like events(messages or transactions) from L1.

The Database<Description> type has a generic Description that implements the DatabaseDescription trait:

/// The description of the database that makes it unique.
pub trait DatabaseDescription: 'static + Clone + Debug + Send + Sync {
    /// The type of the column used by the database.
    type Column: StorageColumn + strum::EnumCount + enum_iterator::Sequence;
    /// The type of the height of the database used to track commits.
    type Height: Copy;

    /// Returns the expected version of the database.
    fn version() -> u32;

    /// Returns the name of the database.
    fn name() -> &'static str;

    /// Returns the column used to store the metadata.
    fn metadata_column() -> Self::Column;

    /// Returns the prefix for the column.
    fn prefix(column: &Self::Column) -> Option<usize>;
}

Each database has its folder, defined by the DatabaseDescription::name, where actual data is stored.

Each database has its own Column type that describes all columns, avoiding overlaps with other tables. The change updates a little bit StrucutredStorage implementation and TableWithBlueprint to be more flexible and use the Column defined by the table, instead of hardcoded fuel_core_storage::column::Column.

Other small changes:

• Unified the logic of storing the database's metadata. It will be useful for Move the DatabaseTransaction logic into StorageTransaction #1589 to implement a unified commit_chagnes function.
• The latest_height function now uses the height from the metadata table.
• Removed relayers-related tables and columns from the fuel-core-storage crate.
• Removed part of GraphQL tables and columns from the fuel-core-storage. The last part will be removed during Move off-chain database updates from storage trait to off-chain worker #1583.
• Moved tx_count metrics from BlockImporter to GraphQL off-chain worker. Any statistic that requires a persistent state in the database may be done outside of the blockchain.
• Remove chain_name from the database. The ConsensusParameters already contains this information.
• Removed the checkpoint function from the RocksDB since it is not used. Later it will be added again back but with another implementation during Move the DatabaseTransaction logic into StorageTransaction #1589.
• Removed Column::ForeignColumn, since each database has its own Column type. Removed the macro rules added to handle ForeignColumn.

[MitchTurner]

Looks like you completed this TODO.

[xgreenx]

No, that one we will be able to remove with #1589 =)

[MitchTurner]

Oh. Lol. Misread that. NVM. I thought the Mutex was gone. Clearly not.

[MitchTurner]

🎆

[MitchTurner]

Looks like it's just that one comment that needs to be removed. Otherwise LGTM.