feat: add support for ink! contracts (#1015)

* feat: contracts endpoint boilerplate

* add @polkadot/api-contracts

* set this as a post request

* modify post request handler type

* cleanup service

* add contracts controller to the default controller

* boilerplate tests

* set mock data for contracts

* expand request types to include generic P type

* cleanup controlelr with expanded types and clean naming. Add query params

* add query params

* comment out some tests

* expand query params, and fix logic

* fix small grumble

* add validateAddress middleware

* pass the ContractPromise into the service to make testing possible

* add test for contracts ink

* fix versions

* cleanup contract query calls

* fix inline comments, and cleanup code

* remove parseBNorThrow (only needed for contrcuting contract txs)

* docs

* update 400 errors

Co-authored-by: marshacb <[email protected]>