herdr web ui v0.2.0

Added

• Remote PCs over SSH: Add PC walks through the host fingerprint, password or key passphrase and
  an approved install, then groups workspaces by PC. Chat, files, images, terminal input and alerts
  follow the selected PC.
• Remote runtime bundles for linux-x64, linux-arm64, darwin-x64 and darwin-arm64, published as the
  remote-v1 release and verified by SHA-256.
• Managed app updates: bun run start and the herdr plugin run a supervisor that builds each update
  in a private checkout, restarts after a health check, and rolls back a failed start.
• Updates follow release tags, and Settings → Updates and the header notice show versions
  (v0.2.0) instead of commit ids. The sidebar footer shows the running version.
• herdr plugin installs, which herdr leaves as a shallow detached checkout, can now update in place.
• INSTALL.md, a step-by-step install guide written for coding agents.

Changed

• Warm terminal redesign: amber on graphite (dark) and ledger paper (light), with agent states in
  their own colors. Sidebar titles use the full width, PC headers fit on one line, user chat turns
  are neutral cards, and the composer placeholder is short.
• The header drops the version pill and the theme toggle. The version is in the connection chip's
  tooltip and the sidebar footer, and theme lives in Settings and the command palette.
• README rewritten around setup, remote PCs, mobile use and updates.

Fixed

• Codex transcripts resolve on macOS, where /proc does not exist.
• Underscores inside identifiers (MAC_QA_CHAT_OK) stay literal in rendered Markdown.
• The settings shortcut table no longer splits its row rules.