fix: token selector issues (#6358)

## Explanation

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The format for EVM addresses for AccountTrackerController in mobile
differs from extension and from the other controller states. This was
causing it to miss native account balances.

It also uses the correct internal account type in the assets, so that
BTC account types can be identified.

Finally, it fixes an issue with the `mergeAssets` function mutating
internal parts of cached objects.

## References

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## Checklist

- [X] I've updated the test suite for new or updated code as appropriate
- [X] I've updated documentation (JSDoc, Markdown, etc.) for new or
updated code as appropriate
- [X] I've communicated my changes to consumers by [updating changelogs
for packages I've
changed](https://github.com/MetaMask/core/tree/main/docs/contributing.md#updating-changelogs),
highlighting breaking changes as necessary
- [X] I've prepared draft pull requests for clients and consumer
packages to resolve any breaking changes

Author: bergarces

packages/assets-controllers/CHANGELOG.md

@@ -10,6 +10,12 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Changed
 
 - Bump `@metamask/base-controller` from `^8.1.0` to `^8.2.0` ([#6355](https://github.com/MetaMask/core/pull/6355))
+- Uses the correct internal account type for the asset ([#6358](https://github.com/MetaMask/core/pull/6358)).
+
+### Fixed
+
+- Ensure that the evm addresses used for an internal mapping are always lowercase to avoid mismatches with client format ([#6358](https://github.com/MetaMask/core/pull/6358)).
+- Prevents mutation of memoized fields, which was causing issues ([#6358](https://github.com/MetaMask/core/pull/6358)).
 
 ## [74.0.0]