Subtitle Drift Correction - Align Two Timing Anchors

Correct a constant subtitle timing drift using two original and corrected anchors, then reparse and download the retimed SRT.

Formula: corrected time = original time × (new₂ − new₁)/(old₂ − old₁) + offset. Cues are rounded to milliseconds. Original text is retained; review warnings before use.

This corrects linear timing drift. Different edits or missing scenes may require separate cue editing. Unicode text is preserved; VTT positioning and unsupported styling are not retained in SRT.