feat: add requestPeriodicUpdate method to SnapRegistryController

[Mrtenz]

Summary

Adds a periodicFetchThreshold option (default: 4 hours) and a public requestPeriodicUpdate method to SnapRegistryController.

The new method is similar to requestUpdate, but skips the update if the registry was fetched within the periodic threshold. This is useful for callers that want to keep the registry reasonably up to date on a longer interval (e.g., on wallet unlock) without triggering a fetch on every call.

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Note

Low Risk
Additive API and config with tests; existing requestUpdate behavior is unchanged.

Overview
Adds requestPeriodicUpdate on SnapRegistryController so callers can refresh the snap allowlist registry on a longer cadence (default 4 hours) without hitting the existing 5-minute “recent fetch” guard used by requestUpdate.

The controller gains a configurable periodicFetchThreshold and refactors #wasRecentlyFetched to accept an optional threshold. When the last fetch is still inside that window, requestPeriodicUpdate no-ops and publishes registryUpdated with false; otherwise it delegates to requestUpdate. Messenger action types and unit tests cover first fetch, skip-within-threshold, and fetch-after-threshold behavior.

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 98.58%. Comparing base (9467ef5) to head (c9343e1).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #4043   +/-   ##
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  Coverage   98.58%   98.58%           
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  Files         425      425           
  Lines       12364    12371    +7     
  Branches     1948     1950    +2     
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+ Hits        12189    12196    +7     
  Misses        175      175           

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[cursor]

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

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