dev: fix deployer Dockerfile (#1512)

Fixes issues with deployer Dockerfile:
- .env must be copied
- issues when building sol contracts due to starknet -> Starknet
capitalization

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docker/deployer/Dockerfile

@@ -55,6 +55,7 @@ ARG GITHUB_TOKEN
 ENV GITHUB_TOKEN=${GITHUB_TOKEN}
 
 COPY . .
+COPY .env.example .env
 
 SHELL ["/bin/bash", "-c"]
 RUN  source "$HOME/.cargo/env" && uv venv && uv pip install -e .

solidity_contracts/src/Starknet/StarknetMessagingLocal.sol

@@ -1,7 +1,7 @@
 // SPDX-License-Identifier: Apache-2.0.
 pragma solidity ^0.8.0;
 
-import "../Starknet/StarknetMessaging.sol";
+import "./StarknetMessaging.sol";
 
 /**
    @notice Interface related to local messaging for Starknet.