feat(docs): add link to fce-sign to guide (#1320)

Author: nikerzetic-aflabs

docs/fcc/guides/01-sign.mdx

@@ -12,6 +12,7 @@ unlisted: false
 
 Build and deploy a **Trusted Execution Environment (TEE) extension** that securely stores a private key and signs arbitrary messages.
 This guide walks through every step — from writing the smart contract and extension handler to deploying on Coston2 and running an end-to-end test.
+The code for this example is available on [GitHub](https://github.com/flare-foundation/fce-sign).
 
 :::info[New to Flare TEE?]
 A TEE extension is an offchain program that runs inside a Trusted Execution Environment.
@@ -47,7 +48,7 @@ The tunnel ([Cloudflared](https://developers.cloudflare.com/cloudflare-one/conne
 Before you begin, make sure you have the following installed:
 
 - [Docker](https://docs.docker.com/get-docker/) and Docker Compose.
-- [Foundry](https://book.getfoundry.sh/getting-started/installation) (`forge`, `cast`) for contract compilation and verification.
+- [Foundry](https://book.getfoundry.sh/getting-started/installation) for contract compilation and verification.
 - [cloudflared](https://developers.cloudflare.com/cloudflare-one/connections/connect-networks/downloads/) to expose a local port to the internet (no account required), or [ngrok](https://ngrok.com/) (requires sign-up).
 - A funded Coston2 wallet with C2FLR for gas and TEE registration fees — use the [Coston2 faucet](https://faucet.flare.network/coston2).
 - Language-specific requirements: