Bezier-rs: Subpath offset and bezier offset improvements (#1039)

* Added subpath offset

* Enhanced offset to produce smooth curves

* Lots of outline bugfixes

* Fixed failing unit tests

* Added subpath outline

* Refactor bezier offset and outline to return Subpaths

* Fix outline bug due to smooth joining and removed reduce optimization that causes jumping approximations

* Bugfix when subpath angle is acute but doesn't intersect

* Stylistic changes per review

* Stylistic changes per review and updated doc comments

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Co-authored-by: Hannah Li <hannahli2010@gmail.com>
Co-authored-by: Keavon Chambers <keavon@keavon.com>

libraries/bezier-rs/src/lib.rs

@@ -1,5 +1,4 @@
 //! Bezier-rs: A Bezier Math Library for Rust
-#[cfg(test)]
 pub(crate) mod compare;
 
 mod bezier;
@@ -9,4 +8,4 @@ mod utils;
 
 pub use bezier::*;
 pub use subpath::*;
-pub use utils::{SubpathTValue, TValue};
+pub use utils::{Joint, SubpathTValue, TValue};