copy-bundled-plugins.cjs compiled and rewrote plugin backend TS in
place, copied it to dist/plugins, but never deleted the .js it had
just emitted next to the .ts sources. Those files shadowed the real
source for vitest/tsx and had import paths rewritten for the dist
layout, so tests failed with "Cannot find module" once a local build
had run. Affects docker, host-metrics and ai, not just this one.
Moves docker backend and frontend into plugins/docker/, alongside
ssh-terminal. Adds a host editor tab seam, a dashboard card registry,
and a build step to compile plugin backends into dist.
LukeGus