feat: update structured output to multiline input and revise system prompt (#8585)

* Update structured_output.py

* [autofix.ci] apply automated fixes

* Update structured_output.py

* [autofix.ci] apply automated fixes

* [autofix.ci] apply automated fixes (attempt 2/3)

* update to prompt

* template updates

* Update src/backend/base/langflow/components/processing/structured_output.py

* [autofix.ci] apply automated fixes

* Update src/backend/base/langflow/components/processing/structured_output.py

* Update src/backend/base/langflow/components/processing/structured_output.py

* Update src/backend/base/langflow/components/processing/structured_output.py

* [autofix.ci] apply automated fixes

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Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>

src/backend/base/langflow/components/processing/structured_output.py

@@ -41,14 +41,13 @@ class StructuredOutputComponent(Component):
             display_name="Format Instructions",
             info="The instructions to the language model for formatting the output.",
             value=(
-                "You are an AI system designed to extract structured information from unstructured text."
-                "Given the input_text, return a JSON object with predefined keys based on the expected structure."
-                "Extract values accurately and format them according to the specified type "
-                "(e.g., string, integer, float, date)."
-                "If a value is missing or cannot be determined, return a default "
-                "(e.g., null, 0, or 'N/A')."
-                "If multiple instances of the expected structure exist within the input_text, "
-                "stream each as a separate JSON object."
+                "You are an AI that extracts one structured JSON object from unstructured text. "
+                "Use a predefined schema with expected types (str, int, float, bool, dict). "
+                "If multiple structures exist, extract only the first most complete one. "
+                "Fill missing or ambiguous values with defaults: null for missing values. "
+                "Ignore duplicates and partial repeats. "
+                "Always return one valid JSON, never throw errors or return multiple objects."
+                "Output: A single well-formed JSON object, and nothing else."
             ),
             required=True,
             advanced=True,