feat: dict based Hyphenation (#305)

## Summary

* Adds (optional) Hyphenation for English, French, German, Russian
languages

## Additional Context

* Included hyphenation dictionaries add approximately 280kb to the flash
usage (German alone takes 200kb)
* Trie encoded dictionaries are adopted from hypher project
(https://github.com/typst/hypher)
* Soft hyphens (and other explicit hyphens) take precedence over
dict-based hyphenation. Overall, the hyphenation rules are quite
aggressive, as I believe it makes more sense on our smaller screen.

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Co-authored-by: Dave Allie <dave@daveallie.com>

lib/Epub/Epub.h

@@ -44,6 +44,7 @@ class Epub {
   const std::string& getPath() const;
   const std::string& getTitle() const;
   const std::string& getAuthor() const;
+  const std::string& getLanguage() const;
   std::string getCoverBmpPath(bool cropped = false) const;
   bool generateCoverBmp(bool cropped = false) const;
   std::string getThumbBmpPath() const;