feat: Introduce Cosmos Scalars (#9933)

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## Description

Closes: #9694

goes hand-in-hand with cosmos/cosmos-proto#17

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- [x] included the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title
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- [ ] added a changelog entry to `CHANGELOG.md`
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- [ ] confirmed `!` in the type prefix if API or client breaking change
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CHANGELOG.md

@@ -39,6 +39,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 
 ### Features
 
+* [\#9933](https://github.com/cosmos/cosmos-sdk/pull/9933) Introduces the notion of a Cosmos "Scalar" type, which would just be simple aliases that give human-understandable meaning to the underlying type, both in Go code and in Proto definitions.
 * [\#9884](https://github.com/cosmos/cosmos-sdk/pull/9884) Provide a new gRPC query handler, `/cosmos/params/v1beta1/subspaces`, that allows the ability to query for all registered subspaces and their respective keys.
 * [\#9860](https://github.com/cosmos/cosmos-sdk/pull/9860) Emit transaction fee in ante handler fee decorator. The event type is `tx` and the attribute is `fee`.
 * [\#9776](https://github.com/cosmos/cosmos-sdk/pull/9776) Add flag `staking-bond-denom` to specify the staking bond denomination value when initializing a new chain.