chore: warn when associate_wallet idempotency_key exceeds 200 chars

Parity with node-sdk. Server truncates at 200 chars; two distinct keys
sharing the first 200 chars would silently dedup. Emit a logger.warning
on the "agentscore" logger so this is visible in dev without changing
behavior (still sends the full key; server truncates).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: vvillait88

agentscore/client.py

@@ -1,12 +1,19 @@
 from __future__ import annotations
 
+import logging
 from importlib.metadata import version as _pkg_version
 from typing import TYPE_CHECKING, Any
 
 import httpx
 
 from agentscore.errors import AgentScoreError
 
+logger = logging.getLogger("agentscore")
+
+# Server truncates idempotency_key at 200 chars; warn the caller past that so two
+# distinct payments that share the first 200 chars don't silently dedup.
+_IDEMPOTENCY_KEY_MAX = 200
+
 if TYPE_CHECKING:
     from agentscore.types import (
         AssessResponse,
@@ -209,6 +216,11 @@ def associate_wallet(
         # Truthy check (not `is not None`) so empty strings don't ship a useless key — mirrors
         # node-sdk's behavior of only forwarding when the key actually has content.
         if idempotency_key:
+            if len(idempotency_key) > _IDEMPOTENCY_KEY_MAX:
+                logger.warning(
+                    "associate_wallet: idempotency_key longer than %d chars will be truncated server-side.",
+                    _IDEMPOTENCY_KEY_MAX,
+                )
             body["idempotency_key"] = idempotency_key
         client = self._get_sync_client()
         response = client.post("/v1/credentials/wallets", json=body)
@@ -316,6 +328,11 @@ async def aassociate_wallet(
         # Truthy check (not `is not None`) so empty strings don't ship a useless key — mirrors
         # node-sdk's behavior of only forwarding when the key actually has content.
         if idempotency_key:
+            if len(idempotency_key) > _IDEMPOTENCY_KEY_MAX:
+                logger.warning(
+                    "aassociate_wallet: idempotency_key longer than %d chars will be truncated server-side.",
+                    _IDEMPOTENCY_KEY_MAX,
+                )
             body["idempotency_key"] = idempotency_key
         client = self._get_async_client()
         response = await client.post("/v1/credentials/wallets", json=body)