fix(AI field): fix KeyError exception generating AI formula (baserow#4505)

Author: silvestrid

changelog/entries/unreleased/bug/keyerror_generating_formula.json

@@ -0,0 +1,9 @@
+{
+    "type": "bug",
+    "message": "Handle KeyError exception when generating formulas with AI.",
+    "issue_origin": "github",
+    "issue_number": null,
+    "domain": "database",
+    "bullet_points": [],
+    "created_at": "2025-12-24"
+}

premium/backend/src/baserow_premium/fields/handler.py

@@ -73,7 +73,7 @@ def generate_formula_with_ai(
         )
         try:
             return output_parser.parse(response)["formula"]
-        except (OutputParserException, TypeError) as e:
+        except (OutputParserException, TypeError, KeyError) as e:
             raise AiFieldOutputParserException(
-                "The model didn't respond with the correct output. " "Please try again."
+                "The model didn't respond with the correct output. Please try again."
             ) from e