feat(bank): update bank.Metadata - add URI and URIHash (#9618)

## Description

Closes: #9502

---

### Author Checklist

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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
- [x] added `!` to the type prefix if API or client breaking change
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- [x] provided a link to the relevant issue or specification
- [x] followed the guidelines for [building modules](https://github.com/cosmos/cosmos-sdk/blob/master/docs/building-modules)
- [ ] included the necessary unit and integration [tests](https://github.com/cosmos/cosmos-sdk/blob/master/CONTRIBUTING.md#testing)
- [ ] added a changelog entry to `CHANGELOG.md`
- [x] included comments for [documenting Go code](https://blog.golang.org/godoc)
- [x] updated the relevant documentation or specification
- [x] reviewed "Files changed" and left comments if necessary
- [ ] confirmed all CI checks have passed

### Reviewers Checklist

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I have...

- [ ] confirmed the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title
- [ ] confirmed `!` in the type prefix if API or client breaking change
- [ ] confirmed all author checklist items have been addressed 
- [ ] reviewed state machine logic
- [ ] reviewed API design and naming
- [ ] reviewed documentation is accurate
- [ ] reviewed tests and test coverage
- [ ] manually tested (if applicable)

CHANGELOG.md

@@ -40,6 +40,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 ### Features
 
 * [\#9533](https://github.com/cosmos/cosmos-sdk/pull/9533) Added a new gRPC method, `DenomOwners`, in `x/bank` to query for all account holders of a specific denomination.
+* (bank) [\#9618](https://github.com/cosmos/cosmos-sdk/pull/9618) Update bank.Metadata: add URI and URIHash attributes.
 
 ### API Breaking Changes
 

docs/core/proto-docs.md

@@ -1567,6 +1567,8 @@ a basic token.
 | `display` | [string](#string) |  | display indicates the suggested denom that should be displayed in clients. |
 | `name` | [string](#string) |  | name defines the name of the token (eg: Cosmos Atom) |
 | `symbol` | [string](#string) |  | symbol is the token symbol usually shown on exchanges (eg: ATOM). This can be the same as the display. |
+| `uri` | [string](#string) |  | URI to a document (on or off-chain) that contains additional information. Optional. |
+| `uri_hash` | [string](#string) |  | URIHash is a sha256 hash of a document pointed by URI. It's used to verify that the document didn't change. Optional. |
 
 
 
@@ -1709,16 +1711,21 @@ GenesisState defines the bank module's genesis state.
 <a name="cosmos.bank.v1beta1.DenomOwner"></a>
 
 ### DenomOwner
-
 DenomOwner defines structure representing an account that owns or holds a
 particular denominated token. It contains the account address and account
 balance of the denominated token.
 
+
 | Field | Type | Label | Description |
 | ----- | ---- | ----- | ----------- |
 | `address` | [string](#string) |  | address defines the address that owns a particular denomination. |
 | `balance` | [cosmos.base.v1beta1.Coin](#cosmos.base.v1beta1.Coin) |  | balance is the balance of the denominated coin for an account. |
 
+
+
+
+
+
 <a name="cosmos.bank.v1beta1.QueryAllBalancesRequest"></a>
 
 ### QueryAllBalancesRequest
@@ -8310,3 +8317,4 @@ still be used for delegating and for governance votes even while locked.
 | <a name="bool" /> bool |  | bool | boolean | boolean | bool | bool | boolean | TrueClass/FalseClass |
 | <a name="string" /> string | A string must always contain UTF-8 encoded or 7-bit ASCII text. | string | String | str/unicode | string | string | string | String (UTF-8) |
 | <a name="bytes" /> bytes | May contain any arbitrary sequence of bytes. | string | ByteString | str | []byte | ByteString | string | String (ASCII-8BIT) |
+

proto/cosmos/bank/v1beta1/bank.proto

@@ -89,4 +89,9 @@ message Metadata {
   // symbol is the token symbol usually shown on exchanges (eg: ATOM). This can
   // be the same as the display.
   string symbol = 6;
+  // URI to a document (on or off-chain) that contains additional information. Optional.
+  string uri = 7 [(gogoproto.customname) = "URI"];
+  // URIHash is a sha256 hash of a document pointed by URI. It's used to verify that
+  // the document didn't change. Optional.
+  string uri_hash = 8 [(gogoproto.customname) = "URIHash"];
 }