fix: Type fixes and optimizations for EngineService, Redux store

[MajorLift]

Description

• Define types: ReduxStore, ReduxState (superseded by chore: Chore/12435 mvp handle engine does not exist #12538)
• Fix any types in EngineService.
• Optimize EngineService event subscriptions:
  • Fix update_bg_state_cb callback being re-defined on every iteration.
  • Consolidate stateChange events collections into BACKGROUND_STATE_CHANGE_EVENT_NAMES constant for maintainability.

Related issues

• Blocked by chore(deps): Bump @metamask/composable-controller from ^3.0.0 to ^10.0.0 #10441
  • Blocked by [composable-controller] perf: Optimize expensive reduce operations, fix metadata instantiation core#4968 and corresponding release.

Manual testing steps

Screenshots/Recordings

Pre-merge author checklist

• I’ve followed MetaMask Contributor Docs and MetaMask Mobile Coding Standards.
• 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 format if applicable
• I’ve applied the right labels on the PR (see labeling guidelines). 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 as recordings and or screenshots.

[github-actions]

CLA Signature Action: All authors have signed the CLA. You may need to manually re-run the blocking PR check if it doesn't pass in a few minutes.

[Cal-L]

nice, LGTM

The base branch was changed.

[github-actions]

Bitrise

✅✅✅ pr_smoke_e2e_pipeline passed on Bitrise! ✅✅✅

Commit hash: 1f5952e
Build link: https://app.bitrise.io/app/be69d4368ee7e86d/pipelines/b6c73799-4380-409d-bd9c-9707d57dad45

Note

• You can kick off another pr_smoke_e2e_pipeline on Bitrise by removing and re-applying the Run Smoke E2E label on the pull request

[github-actions]

Bitrise

✅✅✅ pr_smoke_e2e_pipeline passed on Bitrise! ✅✅✅

Commit hash: c2e4ecb
Build link: https://app.bitrise.io/app/be69d4368ee7e86d/pipelines/5bb01586-8729-4caa-82a1-1347634352ed

Note

• You can kick off another pr_smoke_e2e_pipeline on Bitrise by removing and re-applying the Run Smoke E2E label on the pull request

[sonarcloud]

Quality Gate passed

Issues
3 New issues
0 Accepted issues

Measures
0 Security Hotspots
83.3% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud