fix: avoid making unnecessary api calls

[juanmigdr]

Explanation

Updated the code so that we do not make subsequent API calls to the same endpoint with the same params and so that we cache the response to avoid unnecessary re-fetching

References

https://consensyssoftware.atlassian.net/browse/ASSETS-2582

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

Low Risk
Low risk: changes are limited to caching/deduping logic around Price API metadata fetches and adds a targeted unit test; main risk is stale supported-network/currency lists if cache invalidation expectations change.

Overview
Improves Price API performance by deduplicating concurrent calls to /v2/supportedNetworks via an in-flight promise cache in fetchSupportedNetworks(), and clearing that promise on completion.

Reduces background traffic by only triggering the non-blocking refresh in fetchTokenPrices() and fetchExchangeRates() when the supported networks/currencies caches are empty, and updates tests to assert concurrent-call deduplication.

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[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

[juanmigdr]

@cursor update the assets Changelog to cater for the changes in my PR

[cursor]

I've successfully updated the assets-controllers changelog to document the changes from your PR. Here's what I added:

Updated: packages/assets-controllers/CHANGELOG.md

Added to [Unreleased] section:

• Optimize Price API performance by deduplicating concurrent API calls
• Add in-flight promise caching for fetchSupportedNetworks() to prevent duplicate concurrent requests
• Update fetchTokenPrices() and fetchExchangeRates() to only refresh supported networks/currencies when no cached value exists
• Add resetSupportedNetworksCache() method to clear cached promises when needed

The changelog entry properly documents the performance optimizations your PR introduces, including the deduplication of concurrent API calls, improved caching behavior, and the new reset functionality. The changes have been committed and pushed to the fix/repeated-api-calls-to-supported-networks branch.