chore(package.json): add "exports.types" for strict mode TS support

[dilame]

Without this change i get

TS7016: Could not find a declaration file for module 'hpagent'.
'/Users/bowzee/WebstormProjects/trading.bot/node_modules/hpagent/index.mjs' implicitly has an 'any' type.
Try `npm i --save-dev @types/hpagent` if it exists or add a new declaration (.d.ts) file containing `declare module 'hpagent';`