fix: resolve Stainless SDK regressions and doc example mismatch

- Rename operationId from listFeeRules to getFeeRules to avoid
  Stainless auto-detecting the endpoint as paginated (matches the
  getExchangeRates convention for non-paginated collections)
- Reorder paths: /fee-rules/report before /fee-rules/{feeRuleId}
  so the literal path precedes the parameterized one
- Add missing RAMP_OFF line item to the doc snippet fee report
  example so the total (128,450) matches the sum of line items
- Remove unused gridBaseUrl import from the snippet

Co-authored-by: Cursor <cursoragent@cursor.com>

Author: jaymantri

mintlify/openapi.yaml

@@ -1,5 +1,3 @@
-import { gridBaseUrl } from '/snippets/variables.mdx';
-
 Platform fee rules let you define the markup your platform charges customers on
 each transaction type. Fees are layered on top of Lightspark and counterparty
 fees, and collected in real time during settlement.
@@ -144,6 +142,12 @@ curl https://api.lightspark.com/grid/2025-10-13/fee-rules/report?month=2026-02 \
       "transactionCount": 245,
       "platformFeesCollected": 62500,
       "currency": "USD"
+    },
+    {
+      "transactionType": "RAMP_OFF",
+      "transactionCount": 58,
+      "platformFeesCollected": 14650,
+      "currency": "USD"
     }
   ]
 }