docs: document forge-std version requirements (#290)

Signed-off-by: Luis Mastrangelo <luis@swirldslabs.com>

Author: acuarica

FAQ.md

@@ -26,6 +26,26 @@ That is why when trying to get the code, for example using `cast code --rpc-url
 address of the HTS System Contract, you get `0xfe`.
 That leads to the error `EvmError: InvalidFEOpcode` mentioned in the question.
 
+### Why am I getting error "`Member "keyExistsJson" not found or not visible`" when compiling my project?
+
+If you get the following error when compiling your project
+
+```console
+$ forge build
+[...]
+Error: Compiler run failed:
+Error (9582): Member "keyExistsJson" not found or not visible after argument-dependent lookup in contract Vm.
+```
+
+it is because your `forge-std` dependency is outdated.
+You can [update](https://book.getfoundry.sh/reference/forge/forge-update) `forge-std` with
+
+```sh
+forge update lib/forge-std
+```
+
+See [_§ Requirements_](./README.md#requirements) for the full list of requirements needed to compile your project.
+
 ## Hardhat
 
 ### What causes the error `ProviderError: No known hardfork for execution`

README.md

@@ -46,6 +46,12 @@ First, install our library in your Foundry project
 forge install hashgraph/hedera-forking
 ```
 
+#### Requirements
+
+Ensure your project meets the following requirements
+
+- `forge-std` [`>= v1.8.0`](https://github.com/foundry-rs/forge-std/releases/tag/v1.8.0)
+
 ### Set up
 
 To use this library in your tests, you need to enable [`ffi`](https://book.getfoundry.sh/cheatcodes/ffi).
@@ -183,7 +189,6 @@ Foundry allows you to run Solidity Scripts to interact with a remote network usi
 See [_Scripting with Solidity_](https://book.getfoundry.sh/guides/scripting-with-solidity) for more information on the topic.
 
 To enable Foundry Scripts to work with HTS, you can use `htsSetup()` as described in the previous section.
-You can include
 For example
 
 ```solidity examples/foundry-hts/script/CreateToken.s.sol
@@ -252,6 +257,10 @@ previewnet = "https://previewnet.hashio.io/api"
 localnode = "http://localhost:7546"
 ```
 
+> [!IMPORTANT]
+> Make sure to include the `--skip-simulation` flag when running `forge script`.
+> Otherwise you will get [`EvmError: InvalidFEOpcode`](./FAQ.md#what-causes-the-error-evmerror-invalidfeopcode).
+
 ## Hardhat plugin
 
 We provide a Hardhat plugin that enables fork testing when using HTS Tokens.