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## **Description**

patch assets controller 7.0.0

core PRs: 

- MetaMask/core#8789
- MetaMask/core#8781
- MetaMask/core#8786

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## **Changelog**

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CHANGELOG entry:  patch assets controller 7.0.0

## **Related issues**

Fixes:

## **Manual testing steps**

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## **Screenshots/Recordings**

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## **Pre-merge author checklist**

- [ ] I've followed [MetaMask Contributor
Docs](https://github.com/MetaMask/contributor-docs) and [MetaMask
Extension Coding
Standards](https://github.com/MetaMask/metamask-extension/blob/main/.github/guidelines/CODING_GUIDELINES.md).
- [ ] I've completed the PR template to the best of my ability
- [ ] I’ve included tests if applicable
- [ ] I’ve documented my code using [JSDoc](https://jsdoc.app/) format
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- [ ] I’ve applied the right labels on the PR (see [labeling
guidelines](https://github.com/MetaMask/metamask-extension/blob/main/.github/guidelines/LABELING_GUIDELINES.md)).
Not required for external contributors.

## **Pre-merge reviewer checklist**

- [ ] I've manually tested the PR (e.g. pull and build branch, run the
app, test code being changed).
- [ ] I confirm that this PR addresses all acceptance criteria described
in the ticket it closes and includes the necessary testing evidence such
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<!-- CURSOR_SUMMARY -->
---

> [!NOTE]
> **Medium Risk**
> Touches token/native balance normalization and default asset metadata
keying; mistakes could lead to incorrect balances or duplicate/missing
asset entries in state.
> 
> **Overview**
> Applies a Yarn patch override for `@metamask/assets-controller@7.0.0`
and updates the lockfile to use the patched package.
> 
> The patch tightens `RpcDataSource` balance conversion by validating
`decimals` and raw balances (defaulting invalid values to `"0"`), and
only reuses existing asset metadata when it has valid `decimals` (with a
helper to pick the first valid decimals source).
> 
> It also standardizes default/native asset identifiers: `mUSD` defaults
now use an EIP-55 checksummed address and `DEFAULT_ASSET_METADATA` keys
are stored/queried as checksummed CAIP-19 IDs (no `.toLowerCase()`), and
`buildNativeAssetsFromConstant` now runs IDs through `normalizeAssetId`.
> 
> <sup>Reviewed by [Cursor Bugbot](https://cursor.com/bugbot) for commit
58b729d. Bugbot is set up for automated
code reviews on this repo. Configure
[here](https://www.cursor.com/dashboard/bugbot).</sup>
<!-- /CURSOR_SUMMARY -->