⚡ Bolt: [performance improvement] optimize output parsing in python generator

[cloudesize67-cmd]

💡 What: Replaced intermediate .collect::<Vec<&str>>() allocations with direct iterator pattern matching (.next()) when parsing formatter output in xdk-build/src/python.rs. Replaced string-based splits split("\n") with character-based splits split('\n').
🎯 Why: Avoids unneeded vector allocations on the heap for every line of formatter output, improving the performance of the Python SDK generator.
📊 Impact: Reduces peak memory usage and marginally improves execution speed by eliminating redundant heap allocations in a loop.
🔬 Measurement: Verified with make check and make test-generator. Memory profiles under load would show fewer transient allocations.

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PR created automatically by Jules for task 6020204471636444056 started by @cloudesize67-cmd

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