multi: pull bip300301_wallet into enforcer

1. Rename `Bip300` to `Validator`, to make it clearer what this does.
2. Copy over the wallet implementation from the `bip300301_wallet` repo.
3. Replaced usage of the `bs58` library with `rust-bitcoin`, since this
   is already in the dependency tree through BDK
4. Same goes for the `bip39` library
5. Note that we're using an outdated version of `cusf_sidechain_proto`.
   This is to minimize the changes done here.
6. Note that none of this is tested, nor exposed anywhere. This is also
   to minimize the changes needed in copying over the wallet.

Co-authored-by: Nikita Chashchinskii <nikita.chashchinskii@gmail.com>

.github/workflows/check_lint_build_release.yaml

@@ -11,6 +11,9 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
+        with:
+          submodules: "recursive"
+
       - uses: dtolnay/rust-toolchain@master
         with:
           toolchain: stable
@@ -79,6 +82,8 @@ jobs:
     timeout-minutes: 20
     steps:
       - uses: actions/checkout@v4
+        with:
+          submodules: "recursive"
 
       - name: Install latest stable toolchain
         uses: dtolnay/rust-toolchain@master

.gitmodules

@@ -0,0 +1,3 @@
+[submodule "cusf_sidechain_proto"]
+	path = cusf_sidechain_proto
+	url = https://github.com/LayerTwo-Labs/cusf_sidechain_proto