add validateTxProof and move to contract template

[Pl8tinium]

adds validateTxProof

and

moves the sdk to the contract template repo so we can implement tests

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btw i think we should find a good way to regularly upstream changes from the contract template repo, maybe with github actions and automatic pull request creation? (for all our contract template deriving repos eg btc relay). Maybe smth like this can be useful

https://github.com/tgymnich/fork-sync

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tests dont work, yet

it wants to import the module sdk, but as we are in the actual sdk we may have some circular dependency problem going on here and need to provide some workaround for this specific repo

problem is probably tied to the sdk mock injection for the tests

i tried to play a bit with the asconfig, without success

[user] sdk (feature/addValidateTxProof) > npm run test

> @vsc.eco/[email protected] test
> node --experimental-vm-modules ./node_modules/jest/bin/jest.js

(node:7008) ExperimentalWarning: VM Modules is an experimental feature. This feature could change at any time
(Use `node --trace-warnings ...` to show where the warning was created)
 FAIL  tests/index.ts
  TBD
    ✕ TBD (4 ms)

  ● TBD › TBD

    Cannot find module 'sdk' from 'build/debug.js'

      at Resolver._throwModNotFoundError (node_modules/jest-resolve/build/resolver.js:427:11)
          at async Promise.all (index 0)

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tried to merge everything as reasonable as possible, docs and release process shouldnt have any noticable changes

@Geo25rey wont ping u on discord when its not time critical, ait?

[Geo25rey]

Does this work for the @external calls when testing?