feature: introduce a `ITokenFeeFetcher` fallback

[xrsv]

• What kind of change does this PR introduce? (Bug fix, feature, docs update, ...) feature

• What is the current behavior? (You can also link to an open issue here) We currently use one ITokenFeeFetcher implementation to retrieve token fees

• What is the new behavior (if this is a feature change)? we are introducing an optional fallback ITokenFeeFetcher that will be used to retrieve token fee info in case primary fails, or if some tokens are not present in primary. Plan is to use primary for our graphQL provider, then fallback to onchain fetch in case anything goes wrong or missing.

• Other information: a separate PR will follow on routing-api repo

[graphite-app[bot]]

Graphite Automations

"Request reviewers once CI passes on smart-order-router repo" took an action on this PR • (06/12/24)

3 reviewers were added and 1 assignee was added to this PR based on 's automation.