Speed/Latency improvements

Major Perfomance Optimisations

1. 🚀 8x Faster Page Checks: Adjacent page checks are now parallel which made checks upto 8x faster. The concurrency of grouping can be now controlled with a new option --grouping_concurrency along with normal concurrency for generation for much higher customisation to avoid rate-limits
2. 🚀 8x smaller image footprint: Downscaled pages for continuation checks as these checks are only visual integrity checks as opposed to observing text so we can benefit from a bit of downscaling. Pages are ~3-8x smaller than before and upto ~70% faster both in per-call latency and grouping phase
3. 🔍 Improved Multi-page Table detection. To ensure table consitency across pages, which was the most requested feature, we now support this in the base profile. Should result in imrprovement table merges across pages.
4. 🔍 Cache improvements and stability improvements

Full Changelog: v0.2.1...v0.3.0