🔭 Stellar: Add Alt-Az field rotation calculations

[pozar87]

This PR introduces support for calculating field rotation on Alt-Az mounts, which is critical for users of smart telescopes and Alt-Az astrophotography setups.

1. Field Rotation Rate: Implemented the formula $\omega = \omega_e \frac{\cos(\text{lat}) \cos(\text{az})}{\cos(\text{alt})}$ to calculate the instantaneous rotation rate of the field in arcseconds per second.
2. Maximum Exposure Time: Added a utility to determine the maximum exposure duration before field rotation causes star trailing, based on a user-defined pixel tolerance and the specific camera's sensor geometry.
3. Accuracy: Handled the zenith singularity by capping altitude at 89.99 degrees and provided a 1-hour cap for cases with negligible rotation.

Verified with new unit tests covering various coordinates and equipment configurations.

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PR created automatically by Jules for task 11153797102778091791 started by @pozar87

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