* WIP new Metadata type
* Finish basic Metadata impl inc hashing and validation
* remove caching from metadata; can add that higher up
* remove caches
* update retain to use Metadata
* clippy fixes
* update codegen to use Metadata
* clippy
* WIP fixing subxt lib
* WIP fixing tests, rebuild artifacts, fix OrderedMap::retain
* get --all-targets compiling
* move DispatchError type lookup back to being optional
* cargo clippy
* fix docs
* re-use VariantIndex to get variants
* add docs and enforce docs on metadata crate
* fix docs
* add test and fix docs
* cargo fmt
* address review comments
* update lockfiles
* ExactSizeIter so we can ask for len() of things (and hopefully soon is_empty()
* Ensure unique types in codegen
* tweak comment
* Test the duplicate type codegen stuff
* appease clippy
* fix import
* add another test for generics being de-duplicated
* cargo fmt
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Co-authored-by: Niklas Adolfsson <niklasadolfsson1@gmail.com>
James Wilson