Caller must pass `UserPassCredentials` to `FleetNatsScore::user_pass`
— no more `e2e-admin`/`e2e-device` defaults shipped in the library.
The deploy binary reads `HARMONY_FLEET_*` env vars (default namespace
`harmony-fleet-system`) and fails fast when NATS creds aren't set.
Also: `style/dist/` gitignored, `manual_mint/mint.py` moved next to
`nats/callout/` with README + secrets gitignore (the real RSA key
that was sitting untracked has been removed), `architecture_review.md`
moved to `docs/adr/drafts/024-`, three low-value ROADMAP docs deleted.
Updates pre-merge checklist (§1.6, §1.8, §3.1, §5).
Jean-Gabriel Gill-Couture
a4b3d18bd6