* rename usd_opt to usdc_opt in OracleAccountInfos
* use fallbacks when fetching bank+ price in AccountFetcher struct
* feat: add derive_fallback_oracle_keys to MangoGroupContext
* test: properly assert failure CU in test_health_compute_tokens_fallback_oracles
* provide fallback oracle accounts in the rust client
* liquidator: update for fallback oracles
* set fallback config in mango services
* support fallback oracles in rust settler + keeper
* fix send error related to fetching fallbacks dynamically in tcs_start
* drop derive_fallback_oracle_keys_sync
* add fetch_multiple_accounts to AccountFetcher trait
* revert client::new() api
* deriving oracle keys uses account_fetcher
* use client helpers for deriving health_check account_metas
* add health_cache helper to mango client
* add get_slot to account_fetcher
* lint
* cached account fetcher only fetches uncached accounts
* ensure keeper client does not use cached oracles for staleness checks
* address minor review comments
* create unique job keys for CachedAccountFetcher.fetch_multiple_accounts
* fmt
* improve hashing in CachedAccountFetcher.fetch_multiple_accounts
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Co-authored-by: Christian Kamm <mail@ckamm.de>
Lou-Kamades
Christian Kamm