feat: improve error messages for failed agent operations

[JerryIdoko]

This PR addresses Issue #3 by introducing a centralized error decoder for Stellar and Soroban operations.

Key Changes:

• Created \utils/errorDecoder.ts\ to translate Stellar/Horizon result codes and Soroban errors into human-readable messages.
• Integrated the decoder into \lib/contract.ts, \lib/dex.ts, and \�gent.ts.
• Added unit tests for the error decoder in \ ests/unit/utils/errorDecoder.test.ts.

Why:

Users previously received generic error messages like 'Transaction failed with status: 400'. Now, they will see descriptive messages such as 'Account has insufficient funds for this operation' or 'Missing trustline for asset', significantly improving the developer experience.

Resolves #3

[cubic-dev-ai]

1 issue found across 6 files

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="lib/contract.ts">

<violation number="1" location="lib/contract.ts:157">
P2: Rewrapping every failure here discards the original error object, so callers lose the underlying type, stack, and SDK-specific fields.</violation>
</file>

_{Reply with feedback, questions, or to request a fix. Tag @cubic-dev-ai to re-run a review.}

[cubic-dev-ai]

P2: Rewrapping every failure here discards the original error object, so callers lose the underlying type, stack, and SDK-specific fields.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At lib/contract.ts, line 157:

<comment>Rewrapping every failure here discards the original error object, so callers lose the underlying type, stack, and SDK-specific fields.</comment>

<file context>
@@ -149,9 +152,9 @@ import {
-      throw error;
+      const decodedError = decodeStellarError(error);
+      console.error(`Error in contract interaction (${functName}):`, decodedError);
+      throw new Error(`Contract interaction failed: ${decodedError}`);
     }
   };
</file context>