chore: update submodule references and documentation

- Marked submodules ai-mcp-pmm-controller, explorer-monorepo, and smom-dbis-138 as dirty to reflect recent changes.
- Updated documentation to clarify operator script usage, including dotenv loading and task execution instructions.
- Enhanced the README and various index files to provide clearer navigation and task completion guidance.

Made-with: Cursor

x402-api/.env.example

@@ -5,6 +5,9 @@ THIRDWEB_SECRET_KEY=your-thirdweb-secret-key
 # Server wallet that receives payments (must be a valid address)
 SERVER_WALLET_ADDRESS=0x0000000000000000000000000000000000000000
 
+# Optional: use ALL Mainnet (Alltra, 651940) for payments — Alltra-native x402 + USDC (recommended for production)
+X402_USE_ALLTRA=false
+
 # Optional: use Chain 138 for payments (default: false = use Arbitrum Sepolia + USDC for testing)
 # Set to true only after a Chain 138 token supports ERC-2612/ERC-3009. See docs/04-configuration/CHAIN138_X402_TOKEN_SUPPORT.md
 X402_USE_CHAIN_138=false
@@ -12,5 +15,8 @@ X402_USE_CHAIN_138=false
 # Optional: Chain 138 RPC when X402_USE_CHAIN_138=true
 RPC_URL_138=https://rpc-http-pub.d-bis.org
 
+# Optional: Chain 651940 (Alltra) RPC when X402_USE_ALLTRA=true
+CHAIN_651940_RPC_URL=https://mainnet-rpc.alltra.global
+
 # Optional: server port (default 4020)
 PORT=4020