Adds four documents that form the Buckit Manager design corpus
alongside the existing README.md and phase1-web-ui.md:
- phase1-implementation.md: Phase 1 milestone plan (M0-M9), repo
layout, locked stack decisions, and a Progress section that tracks
what's landed in github.com/buckit-io/bm so work can resume cleanly
in a new session.
- ui-architecture.md: data flow (admin API + per-node connectivity
probes + SSH facts), the on-demand fetch pipeline with failure
isolation, REST contract sketch, per-page details for Clusters
list, Cluster detail, History, and Manager Settings, and the
proposed HostInfo extension to madmin.ServerProperties to surface
OS / CPU / Memory / Network in /admin/info.
- metrics.md: spec for the per-cluster Metrics tab (Info, Usage,
Traffic, Resources) — referenced by ui-architecture.md as the
source-of-truth for the existing /admin/info shape.
- authentication.md: notes on Console + mc CLI auth flows.
abuckit