fix: restore clean npm install

[ManuelSalcedo2770]

Summary

• Add a package lock so the SDK has a reproducible npm install path.
• Update eslint-plugin-functional to a release compatible with the repo's ESLint 8 dev dependency.
• Pin @types/node to a TypeScript 4.9-compatible release so the TypeScript build does not resolve newer Node declarations requiring newer TS libs.
• Remove obsolete TypeDoc flags from doc:json.

Why

A clean checkout currently cannot run npm ci because there is no root lockfile, and npm install fails on the ESLint peer dependency mismatch. After generating a lockfile, the build also resolves Node types that are too new for the repo's TypeScript 4.9 setup. This PR keeps the change scoped to dependency/tooling reproducibility.

Verification

• npm ci
• npm run build
• npm run doc:json
• git diff --check

Note: npm test -- --runInBand still requires local bridge configuration values in a clean checkout, so I did not list it as passing verification.

Submitted for the Bitgesell PR bounty hunt: BitgesellOfficial/bitgesell#39. Payout details can be provided after maintainer review/approval.

[MyTH-zyxeon]

Maintainer review-assist for #39:

• Scope looks limited to reproducible npm tooling: adds package-lock.json, updates eslint-plugin-functional for the repo's ESLint 8 setup, pins @types/node to 18.17.19 for TypeScript 4.9 compatibility, and removes obsolete TypeDoc flags from doc:json.
• Current visible state: OPEN, MERGEABLE, CLEAN; no PR comments, reviews, review threads, or public status checks were visible when checked.
• Acceptance checks I would use: fresh checkout npm ci, npm run build, and npm run doc:json; also confirm maintainers are comfortable with npm lockfileVersion 3 for the supported Node/npm baseline.
• Bounty hygiene: the PR body routes this to BGL PR bounty hunt ($10000 overall budget) bitgesell#39, so payout/priority remains a maintainer decision.

No secrets, dependency install, build/test run, local checkout mutation, wallet/key action, live node/RPC call, live-chain action, payment action, or claim submission was performed.