⚡ Bolt: Optimize star coordinate extraction in skymap plotting

[pozar87]

💡 What: Replaced pandas.Series.apply with list comprehensions for extracting coordinates (RA, Dec) and magnitudes from Pint Quantities in the star plotting pipeline (apts/plotting/skymap_objects/stars.py).

🎯 Why: apply has significant overhead for simple attribute access on object-type columns in large DataFrames. List comprehensions over .values are a more efficient way to perform these row-wise operations in Python.

📊 Impact: Measured a ~1.2x speedup in the _ensure_coordinate_columns function. This makes skymap generation faster, especially when processing the full Hipparcos catalog or large sets of bright stars.

🔬 Measurement: Verified using a timeit micro-benchmark on 10,000 mock Pint objects. Functional correctness was confirmed by running the full unit test suite (after compiling localization catalogs).

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PR created automatically by Jules for task 2143935972530827289 started by @pozar87

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