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: #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

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Note

BREAKING: TokenListController persists tokensChainsCache via StorageService using per-chain files; state metadata for tokensChainsCache set to persist: false.

• Adds #initializeFromStorage, #loadCacheFromStorage (parallel per-chain load), #saveChainCacheToStorage, and #migrateStateToStorage
• Updates fetchTokenList to await init, write only the updated chain, and avoid refreshing timestamps on failed fetches
• Makes clearingTokenListData async to remove all per-chain files (with partial-failure handling) and clears state accordingly
• Refactors internals (private # fields, polling stop method) and improves network-change handling
• Adds @metamask/storage-service dependency and tsconfig references; updates changelog
• Expands tests to mock StorageService, cover migration/load/save/clear flows, and adjust for async behaviors

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[sahar-fehri]

Making this false to block disk writes