I was wondering if iog (or some other trusted party) offers
api/cli wallet functionality that does not require installing a node or syncing the whole chain. This would be really helpful for hosting cardano-based small projects on a local server.
Lace seems promising but it appears to be a ui only, Am I right? do you know any other platforms?
There is elastic query layer (not from IO, and not exactly from a company) - Koios, where community can string their instances together, and is open-source. You can use it via one of the two CLI projects or libraries, OR you can directly liase with the REST endpoints.
Dapp connector or bridge wallets that implement CIP-30 may be good enough for your needs as well. Most of which already leverage one of the API options @rdlrt mentioned. Yoroi was supposed to implement this functionality but more popular community wallets are also available. Checkout the CIP-30 compatibility matrix for more details.