Extract storage creation from State Transition Function

[citizen-stig]

Description

This is the first step for implementing reorgs support.

This PR includes:

• Change in rollup-interface StateTransitionFunction, by adding extra types that will needed
• App template does not hold storage anymore, but it still does commit. Extracting commit functionality is under discussion
• ProverStorage only writes to underlying db in commit, and not in compute_state_update. Except for empty JMT case. Added todo for this.
• Adding new StorageManager to rollup-interface which is temporary placeholder before ForkManager arrives:

pub trait StorageManager {
    type NativeStorage;
    type NativeChangeSet;

    fn get_native_storage(&self) -> Self::NativeStorage;
}

Decision to keep AppTemplate committing to database is made for 2 reasons:

• When ProverStorage will be transformed to work over snapshots, then it won't be actual commit to database, but to Snapshot.
• To minimize changes done in this PR. But technically, Storage can become read-only over underlying storage. This is up to discussion. But it will simplify Storage trait a little bit.

Minor changes

• Rename variables app and demo to stf
• Rename generic ST to Stf according to generics naming convention.
• Remove ProverStorage::db() method, as it is used only in tests
• Make runtime attribute from AppTemplate to be crate public instead of completely public, as it was only used for tests.

Linked Issues

• Related to Data Availability re-orgs handling tracking issue #1023

Testing

All existing tests are passing.

Docs

Documentation has been updated

[codecov]

Codecov Report

Merging #1103 (5fa223c) into nightly (9995ada) will decrease coverage by 0.1%.
Report is 2 commits behind head on nightly.
The diff coverage is 92.8%.

Files	Coverage Δ
...tions/integration-tests/src/chain_state/helpers.rs	89.8% <ø> (-0.9%)	⬇️
...tations/integration-tests/src/chain_state/tests.rs	97.0% <100.0%> (+<0.1%)	⬆️
module-system/sov-modules-api/src/state/mod.rs	100.0% <100.0%> (ø)
...dule-system/sov-modules-rollup-template/src/lib.rs	91.5% <100.0%> (-0.3%)	⬇️
module-system/sov-modules-stf-template/src/lib.rs	89.8% <100.0%> (+0.2%)	⬆️
module-system/sov-state/src/lib.rs	84.2% <ø> (ø)
module-system/sov-state/src/prover_storage.rs	93.7% <100.0%> (-1.4%)	⬇️
module-system/sov-state/src/storage.rs	94.3% <ø> (ø)
module-system/sov-state/src/storage_manager.rs	100.0% <100.0%> (ø)
rollup-interface/src/state_machine/stf.rs	85.7% <ø> (ø)
... and 4 more

... and 10 files with indirect coverage changes

[bkolad]

After this is merged, can you please update https://github.com/Sovereign-Labs/sov-rollup-starter as well?