Various performance improvements

[moffatman]

Should be twice as fast according to my use cases. Happy to discuss what you need for testing, (micro)benchmarking, preserving public API for old slow functions, or whatever else to merge it. I know I still need to do stuff like bump version, changelog, etc.

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[kevmoo]

please run the formatter!

[moffatman]

Idk whether the new trie.dart is the right way... maybe something to wait for dart macros

[mosuem]

Closing as the dart-lang/html repository is merged into the dart-lang/tools monorepo. Please re-open this PR there!