feat(core): adding pubdata to statekeeper and merkle tree (#259)

# What ❔

Setting the ground for bigger boojum changes. Adding boojum related
fields to the data model and types. Extending state tree to have a
concept of `StateDiffs`.

## Why ❔

We want to reduce the size of the overall boojum merge, this sets the
basis for more extensive changes. These changes are all meant to be
non-intrusive.

## Checklist

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- [x] PR title corresponds to the body of PR (we generate changelog
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- [x] Tests for the changes have been added / updated.
- [x] Documentation comments have been added / updated.
- [x] Code has been formatted via `zk fmt` and `zk lint`.

---------

Co-authored-by: “perekopskiy” <[email protected]>

core/lib/dal/migrations/20231018205126_l1_batches_boojum_fields.down.sql

@@ -0,0 +1,5 @@
+ALTER TABLE l1_batches
+    DROP COLUMN IF EXISTS system_logs;
+
+ALTER TABLE l1_batches
+    DROP COLUMN IF EXISTS compressed_state_diffs;

core/lib/dal/migrations/20231018205126_l1_batches_boojum_fields.up.sql

@@ -0,0 +1,6 @@
+ALTER TABLE l1_batches
+    ADD COLUMN IF NOT EXISTS system_logs BYTEA[]
+    NOT NULL DEFAULT '{}';
+
+ALTER TABLE l1_batches
+    ADD COLUMN IF NOT EXISTS compressed_state_diffs BYTEA;