Settings → Workflows: edit, rename, and delete existing Workflows #1434

Written-by: Dev

Goal

Existing Workflows must be manageable from Settings → Workflows (and the same plugin surface): edit and delete, not only create + open.

Today

• workflow/create and workflow/graph exist; the flowchart can be edited after Edit.
• There is no workflow/delete (or rename) API, and list rows have no delete / rename / duplicate controls.
• define_workflow can replace a graph by id/name, but Settings does not expose rename or delete of a saved Workflow.

Wanted

1. Delete a saved Workflow (confirm in UI). Clean up its store entry; abort/release any live run Bots for that workflow; remove sidebar/session entry if the plugin owns one. Refuse or confirm clearly when a live run is in progress.
2. Rename (and optional description) of an existing Workflow from Settings / drawer, persisted with the graph.
3. Keep Edit flowchart (nodes, edges, prompts, tools) as today; ensure Finish editing still saves via workflow/graph.
4. Nice-to-have if cheap: Duplicate a Workflow as a new id with a copy of the graph.

Surfaces

• Plugin RPC: add workflow/delete, workflow/rename (or a single workflow/update for name/description) alongside create/graph.
• Browser: Settings → Workflows list + open drawer — actions for rename/delete (and duplicate if done).
• Tests: service + client/page coverage; ZH/EN strings.
• Changelog fragment under changelog.d/.

Out of scope

• Changing the real-run / queue engine (Workflow: real Bot-gated runs, kanban task queue, concurrency, assign to Workflow or Bot #1402 / Run Workflow nodes as ephemeral Bots with a queue, loops and conditions #1412).
• Factory preset deletion (presets stay; only user-owned copies).

Done when

Owner can open an existing Workflow, rename it, edit its graph, and delete it from Settings without hand-editing JSON under $DSH_HOME.