⚡ Optimize check_drift.py: Use any() and tuple prefix matching

[HeadyConnection]

💡 What:

• Replaced inefficient string concatenation " ".join(changed) with any() generator for documentation drift check.
• Optimized watched_changes filtering to use str.startswith(tuple) instead of nested loops.

🎯 Why:

• The original code concatenated all file paths into a single string to check for "docs/" presence, which is memory inefficient and slower for large diffs.
• The watched_changes logic was iterating through prefixes for every file path in python loop.
• These changes significantly improve performance and memory usage.

📊 Measured Improvement:
Benchmark with 100,000 file paths (shuffled):

• Baseline: 3.13s
• Optimized: 0.51s
• Speedup: ~6.1x

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PR created automatically by Jules for task 8613324875979557582 started by @HeadyConnection

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