Display the single-source version (root package.json) in the web UI's
lower-right corner, in grey — matching the CLI and TUI. The browser can't read
the filesystem, so the version flows backend → browser via GET /api/config:
- Add `version?: string` to InitialConfigPayload; the web backend
(webServerConfigToInitialPayload) reads it once via the shared
readInspectorVersion() and tags it onto the payload.
- Add a `useInspectorVersion` hook mirroring useSandboxUrl/useServerListWritable.
- Add a presentational `VersionBadge` element rendered fixed lower-right, grey,
non-interactive; styling lives in a `versionBadge` Text theme variant (no
inline styles, --inspector-* tokens).
- Wire it into App.tsx.
Verified live: /api/config serves `version: "2.0.0"` and the badge renders
`v2.0.0` fixed at the lower-right in grey. Tests: useInspectorVersion (full
branch coverage), VersionBadge (unit + Storybook), web-server-config payload.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01BrihGWcrM9JGRyu41nzZYw
