Add documentation of the EVM support in Linera. (#228)

Add the first version of the documentation of EVM support in Linera.

Author: MathieuDutSik

src/appendix/glossary.md

@@ -22,7 +22,7 @@
   selected at the next block height.
 
 - **Bytecode**: A collection of bytes corresponding to a program that can be run
-  by the Wasm virtual machine.
+  by the virtual machine. This is either a Wasm or EVM bytecode.
 
 - **Client**: The `linera` program, which is a local node and wallet operated by
   users to make requests to the network. In Linera, clients drive the network by

src/developers/advanced_topics/block_creation.md

@@ -18,7 +18,7 @@ several types of chains, depending on how new blocks are produced.
 Instead, the wallets (aka. `linera` clients) of chain owners make the system
 progress by proposing blocks and actively providing any additional required data
 to the validators. For instance, client commands such as `transfer`,
-`publish-bytecode`, or `open-chain` perform multiple steps to append a block
+`publish-module`, or `open-chain` perform multiple steps to append a block
 containing the token transfer, application publishing, or chain creation
 operation:
 

src/developers/experimental/ethereum.md

@@ -0,0 +1,104 @@
+# Using EVM-Based Smart Contracts on Linera
+
+It is possible to use Ethereum Virtual Machine (EVM)-based smart contracts on
+Linera. These contracts are typically written in Solidity.
+
+EVM smart contracts have access Linera-specific functionality of Linera through
+the `Linera.sol` library which exposes necessary interfaces for integration.
+
+This allows smart contracts originally deployed on Ethereum to be migrated to
+Linera and progressively adapted to Linera’s architecture and features.
+
+## Publishing EVM Smart Contracts
+
+The process for publishing EVM smart contracts is similar to that for Wasm smart
+contracts, with the key difference being the need to specify the virtual machine
+used (the default is Wasm).
+
+For EVM contracts, there is only one bytecode file (unlike Wasm, which requires
+separate `contract` and `service` binaries). Therefore, the same file must be
+passed twice:
+
+```bash
+linera publish-and-create \
+  counter.bytecode counter.bytecode \
+  --vm-runtime evm \
+  --json-parameters "42"
+```
+
+Here, `counter.bytecode` contains the compiled contract, and "42" is passed as a
+constructor argument via the `--json-parameters` flag.
+
+Constructor arguments for the EVM contract are passed through application
+parameters. Instantiation-specific arguments are provided separately.
+
+## Calling other smart contracts.
+
+EVM smart contracts on Linera can invoke other EVM contracts using standard
+Solidity syntax.
+
+### EVM Contracts calling Wasm smart contracts.
+
+To call a Wasm smart contract from an EVM contract, use the following Solidity
+command:
+
+```solidity
+	bytes memory return_value = Linera.try_call_application(address, input);
+```
+
+- `address`: the address of the Wasm smart contract, as a `bytes32`.
+- `input`: the bytes representing the BCS-serialized `ContractAbi::Operation`
+  input.
+
+The serialization code can be generated using the `serde-reflection` crate.
+
+### Wasm Smart Contracts calling EVM Contracts.
+
+Wasm smart contracts can call EVM contracts using the `alloy-sol-types` crate.
+This crate enables construction of Solidity-compatible types and supports RLP
+serialization/deserialization.
+
+The Wasm contract call-evm-counter demonstrates this functionality.
+
+- For operations, the input type is `Vec<u8>`.
+
+- For service calls, the input type is `EvmQuery`.
+
+Note: Linera distinguishes between contract and service code execution contexts.
+
+## Multichain EVM applications.
+
+To operate across multiple chains, an EVM application must implement the
+following functions:
+
+```solidity
+    function instantiate(bytes memory input) external
+    function execute_message(bytes memory input) external
+```
+
+- `instantiate` is called on the creator chain.
+
+- `execute_message` handles incoming cross-chain messages.
+
+Additional SDK functions available include:
+
+```solidity
+    Linera.chain_ownership()
+    Linera.read_data_blob()
+    Linera.assert_data_blob_exists()
+    Linera.validation_round()
+    Linera.message_id()
+    Linera.message_is_bouncing()
+```
+
+## Difference between EVM applications in Ethereum and Linera.
+
+- `Reentrancy`: Reentrancy is not supported on Linera. Contracts relying on it
+  will fail with a clean error.
+
+- `Address Computation`: Contract addresses are computed differently from
+  Ethereum.
+
+- `Gas Limits`: Following Infura's practice, Linera imposes a gas limit of
+  20,000,000 for service calls in EVM contracts. Contract execution is similarly
+  constrained.