[codex] move repo into workspace layout and share probe transports

[caryden]

What changed

• moved the repo into a Bun workspace layout with apps/cli, apps/web, apps/desktop, and packages/core
• extracted the node-hid transport into packages/transport-nodehid
• added packages/transport-webhid for the browser path
• added packages/ui for the shared probe UI used by the web and desktop apps
• converted the web and Electrobun PoCs into thin wrappers over shared UI, shared core logic, and transport-specific packages
• updated docs, workspace config, release/build scripts, and local CI to match the new structure

Why

The WebHID and Electrobun PoCs proved the intended architecture:

• shared pure protocol/catalog logic
• shared frontend UI shape
• separate transports for browser WebHID and desktop Node HID

This PR makes that structure explicit in the repo so future UI work can build on stable package boundaries instead of continuing to grow inside ad hoc PoC directories.

Impact

• the CLI still builds as a standalone binary and keeps the current command surface intact
• the web and desktop PoCs now share real code instead of duplicated probe logic
• future UI work can happen in apps/web and apps/desktop without coupling renderer code to the CLI package

Validation

• bun run check
• bun run typecheck
• bun run build
• ./scripts/ci-local.sh
• manual Electrobun dev boot from apps/desktop

[caryden]

Superseded by #82. The workspace/core foundation work is contained in the current direct-to-main branch, so this older stacked PR is being closed to keep the queue clean.