feat: add debug-mode to in-memory-node (#217)

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# Description

Add `Debug Transactions & Smart Contracts` to In-Memory Node docs


![image](https://github.com/user-attachments/assets/86caf3f7-4e8c-4bd7-95db-401890e28732)

content/00.build/60.test-and-debug/20.in-memory-node.md

@@ -88,6 +88,23 @@ As a result, an L1 RPC is not available.
 
 ---
 
+## Debug Transactions & Smart Contracts
+
+The default configuration of `era_test_node` displays minimal data in the terminal to keep the output clean.
+However, if you are having issues with your smart contracts and need more details why a transaction is failing, try enabling `--debug-mode` (or just `-d`).
+
+```bash
+era_test_node -d
+```
+
+This will:
+
+- Show the full call stack and each call's output for transactions
+- Show more details about the breakdown of gas cost per transaction
+- Resolve known hashes into human-readable strings
+
+---
+
 ## Fork a network
 
 To fork the mainnet, use the following command, replacing `[network]` with either `mainnet` or `sepolia-testnet`: