Fix dist package for typescript

[cgewecke]

When you install @setprotocol/set-protocol-v2 from npm, the fixtures etc are currently unusable because TS throws errors like this:

test/manager/baseManagerV2.spec.ts:23:31 - error TS7016: Could not find a declaration file for module '@setprotocol/set-protocol-v2/dist/utils/fixtures/PerpV2Fixture'. '/Users/cgewecke/code/set/set-v2-strategies/node_modules/@setprotocol/set-protocol-v2/dist/utils/fixtures/PerpV2Fixture.js' implicitly has an 'any' type.
  Try `npm i --save-dev @types/setprotocol__set-protocol-v2` if it exists or add a new declaration (.d.ts) file containing `declare module '@setprotocol/set-protocol-v2/dist/utils/fixtures/PerpV2Fixture';`

23 import { PerpV2Fixture } from "@setprotocol/set-protocol-v2/dist/utils/fixtures/PerpV2Fixture";
                                 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

PR:

• changes the tsconfig to generate source and types maps so imports from node_modules behave as expected
• copies typechain folder into the dist folder post-build (as part of npm command)
• updates README with npm package usage example

---

Have checked that this works by publishing to tag tsdebug

yarn add @setprotocol/set-protocol-v2@tsdebug

... and importing the fixture into the repo we've seen this problem in (on the richard/perp... branch) as below:

import { PerpV2Fixture } from "@setprotocol/set-protocol-v2/dist/utils/fixtures/PerpV2Fixture";
import { getPerpV2Fixture } from "@setprotocol/set-protocol-v2/dist/utils/test";

let perpSetup: PerpV2Fixture;
perpSetup = getPerpV2Fixture(...);