Update docs to include Beta 2 content

[Shellishack]

• Add shared utils and react-api docs
• Add workspace (remote and local) docs (e.g. filesystem, terminal environment)
• Add workflow usage and sharing docs
• Add app usage and publishing docs
• Add app development (full-stack) docs (e.g. previewing dev server in workspace container, adding dev app extension)
• Add cli usage docs
• Add editor interface usage docs (e.g. command viewer, menu layout)
• Add canvas view usage docs (e.g. select node, run workflow, view as standlone app)
• Add mobile usage guide
• Add desktop usage guide
• Add web usage guide
• Add self-host workspace docs
• Add usage case docs -- vibe coding
• Add usage case docs -- serverless comfyui + video composing