New node: Merge by Distance (#2307)

* add `merge_by_distance` node

* remove unneeded features of petgraph

Also re-arrange module slightly since because functions are no longer
async, there was name shadowning with the old arrangement.

* remove region if start or end segment is removed

* remove stuff I ended up not using

* "algos" -> "algorithms"

* Code review pass

---------

Co-authored-by: Keavon Chambers <keavon@keavon.com>

node-graph/gcore/Cargo.toml

@@ -50,6 +50,11 @@ glam = { workspace = true, default-features = false, features = [
 	"scalar-math",
 ] }
 serde_json = { workspace = true }
+petgraph = { workspace = true, default-features = false, features = [
+	"graphmap",
+] }
+rustc-hash = { workspace = true }
+math-parser = { path = "../../libraries/math-parser" }
 
 # Required dependencies
 half = { version = "2.4.1", default-features = false, features = ["bytemuck"] }
@@ -77,7 +82,6 @@ web-sys = { workspace = true, optional = true, features = [
 image = { workspace = true, optional = true, default-features = false, features = [
 	"png",
 ] }
-math-parser = { path = "../../libraries/math-parser" }
 
 [dev-dependencies]
 # Workspace dependencies