* Add tokenizer improvments via Singleton class
linting
* dev build
* Estimation fallback when string exceeds a fixed byte size
* Add notice to tiktoken on backend
* implement custom PDFLoader to remove LC dep
* remove unneeded comment
* remove pdfjs as dep and fix page splitting using pdf-parse
* linting + export rename for desktop compat
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Co-authored-by: timothycarambat <rambat1010@gmail.com>
