## Explanation

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## References

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## Checklist

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

<!-- CURSOR_SUMMARY -->
---

> [!NOTE]
> **Medium Risk**
> Primarily dependency/version bumps, but it pulls in **breaking** major
releases of `@metamask/controller-utils@12` and
`@metamask/network-controller@31`, which can break downstream typed
event listeners and service policy handlers.
> 
> **Overview**
> Bumps the monorepo release version to `974.0.0` and rolls forward many
internal package versions/changelogs.
> 
> Most packages are updated to depend on
`@metamask/controller-utils@12.0.0` and
`@metamask/network-controller@31.0.0` (plus related patch bumps like
`@metamask/message-manager@14.1.2`,
`@metamask/polling-controller@16.0.5`, etc.), propagating the new
**breaking** event payload/type changes through the dependency graph.
> 
> <sup>Reviewed by [Cursor Bugbot](https://cursor.com/bugbot) for commit
898f4a8. Bugbot is set up for automated
code reviews on this repo. Configure
[here](https://www.cursor.com/dashboard/bugbot).</sup>
<!-- /CURSOR_SUMMARY -->