Make workflow UI tools headless

[georgi]

What

Make the workflow document ui_* tools usable without a renderer while preserving the existing live-editor behavior.

• Add a pure persisted-graph command adapter for graph read/add/connect/update/delete/move/title operations.
• Expose the same contracts through unified chat, MCP, the CLI toolset, evals, and /ws/agent.
• Prefer the connected renderer when one exists so commands see unsaved canvas state; otherwise fall back to the persisted workflow.
• Add optimistic concurrency with expected_updated_at, including autosave, and refresh clean open editors from resource-change events.
• Preserve collaborator permissions, trigger registration sync, and group-child positions on headless deletion.

Why

The tool contract should describe an operation, not where it runs. A live editor and a headless agent now use the same ui_* names with different adapters selected by availability.

Validation

• Node SDK workflow document tests: 8 passed
• Web refresh policy tests: 4 passed
• Focused TypeScript builds: protocol, node-sdk, models, agents
• Focused TypeScript checks for the new web helper and autosave client
• Oxlint on changed source: no errors
• Manual toolset smoke check confirms all eight document tools are registered
• Database concurrency test could not execute in this environment because the native better-sqlite3 binding is unavailable
• Broader websocket tests could not execute because the workspace dependency install is incomplete in this environment