chore(lint): Fix suppressed ESLint errors in base-controller package

[Mrtenz]

Explanation

This fixes all suppressed ESLint errors in the base-controller package.

References

Closes #7344.

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
• I've introduced breaking changes in this PR and have prepared draft pull requests for clients and consumer packages to resolve them

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Note

Refactors BaseController types and tests to satisfy ESLint by adding explicit return types, refining generics, and cleaning up imports; removes related suppressions.

• Core (packages/base-controller/src/BaseController.ts)
  • Add explicit return types to state getter, applyPatches, destroy, and update result.
  • Rename generic/type params for clarity (T→Type), and tighten typings (StateChangeListener, StateDeriver, StateMetadata).
  • Minor callback param rename in produceWithPatches cast (callbackFn).
• Tests (packages/base-controller/src/BaseController.test.ts)
  • Add explicit return types to controller overrides and helper functions; annotate arrow properties.
  • Switch sinon import to default; reorder imports; add // eslint-disable-next-line no-new where needed.
• Lint config
  • Update eslint-suppressions.json to remove suppressions for base-controller files now addressed.

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