⚡ Bolt: Replace pandas iterrows with to_dict('records') for performance

[alinelena]

💡 What: Replaced slow df.iterrows() pandas iterations with df.to_dict('records') in the data verification pipeline.
🎯 Why: Iterating over large pandas DataFrames using iterrows() is a known performance anti-pattern because it creates a new pandas Series object for each individual row.
📊 Impact: Considerably faster dictionary comprehension and metadata parsing during dataframe iterations.
🔬 Measurement: Verify by running the profiling tools and verifying that building dictionary mappings of the dataframe executes notably faster on large subsets of data.

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PR created automatically by Jules for task 16906350785791920138 started by @alinelena

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