Allow tooling to treat near-zero-length handles as zero-length with an epsilon

[HWienhold]

fixes https://discord.com/channels/731730685944922173/881073965047636018/1353015950894698606

Fixes a bug when connecting two paths ending with single handle (each) and applying colinear handles. on the newly connected nodes. Problem arises because applying colinear handles on the first node will create the opposite handle. The other node then has two handles, one of which is the anchor itself, hence:

let mut handle_directions = handle_positions.map(|handle| handle.map(|handle| handle - anchor));

will contain a null-Vec.

To be fair: this slightly changes the behavior when applying colinear handles to other nodes that only has one handle: while before it wouldnt change that node - now it will calculate the handles based on the anchors as well.

[Keavon]

!build

[github-actions[bot]]

📦 Build Complete for 398e0a817b07b4ccc93b6a1778675948fffaabb7
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