README: local install path appears monorepo-specific and breaks standalone onboarding

[rohdahal]

While testing onboarding from a standalone clone, I noticed the local install path in README appears monorepo-specific:

cd platform-adapters/fathom/fathom-cli

In this repo layout, users are already at fathom-cli, so the command is confusing / fails for standalone usage.

Suggested fix:

• replace with a standalone-safe flow (from repo root):
  • npm install
  • npm link

Context:
I haven’t been able to run live API commands yet because I don’t currently have a Fathom API key, but this docs issue is reproducible without API access.