chore: integrate storageService with tokenListController

[sahar-fehri]

Description

Optimizes TokenListController storage to reduce write amplification by persisting tokensChainsCache via StorageService using per-chain files instead of a single monolithic state property.

Related: https://github.com/MetaMask/metamask-mobile/pull/22943/files

Related: https://github.com/MetaMask/decisions/pull/110

Related: https://github.com/MetaMask/core/pull/7192

Explanation

The tokensChainsCache (~5MB total, containing token lists for all chains) was persisted as part of the controller state. Every time a single chain's token list was updated (~100-500KB), the entire ~5MB cache was rewritten to disk, causing:

• Startup performance issues (loading large state on app initialization)
• Runtime performance degradation (frequent large writes during token fetches)
• Impacts both extension

Solution

Per-Chain File Storage: Each chain's cache is now stored in a separate file (e.g., tokensChainsCache:0x1, tokensChainsCache:0x89) Only the updated chain (~100-500KB) is written on each token fetch, reducing write operations by ~90-95% All chains are loaded in parallel at startup to maintain compatibility with TokenDetectionController Key Changes:

• Set tokensChainsCache metadata to persist: false to prevent framework-managed persistence
• Added #loadCacheFromStorage() to load all per-chain files in parallel on initialization
• Added #saveChainCacheToStorage(chainId) to persist only the specific chain that changed
• Added #migrateStateToStorage() to automatically migrate existing cache data on first launch after upgrade
• Updated clearingTokenListData() to remove all per-chain files

References

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

---

[!NOTE] TokenListController now persists tokensChainsCache to StorageService per-chain with migration, parallel loading, improved error handling, and updated tests; adds StorageService dependency and disables framework persistence for that state.

• TokenListController
  • Persist tokensChainsCache via StorageService using per-chain keys (e.g., tokensChainsCache:0x1); load all chains in parallel at init.
  • Add migration from state to per-chain storage; set state metadata persist: false for tokensChainsCache to avoid duplication.
  • Save only the updated chain on fetch; make clearingTokenListData() async to clear both state and stored per‑chain files; add robust error logging around load/save/clear and network changes.
  • Integrate StorageService actions in messenger; switch to private # fields; export DataCache.
• Tests
  • Add StorageService mock handlers; extensive tests for migration, save/load, error paths; update to await clearingTokenListData(); minor typings fix for getTokensPath.
• Build/Deps/Changelog
  • Add @metamask/storage-service dependency and TS project references; update CHANGELOG.md to document new persistence model.

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