Dynamic tools/abilities from workflow templates #1721

Proposal

Depends on #1720 (workflow templates).

A template can optionally be registered as an ability, or a tool on Hub's MCP (?). Hub exposes the tools. This plugin registers them and runs them.

https://github.com/publishpress/publishpress-hub/issues/246

Example: instead of only a fixed tool/ability such as future_schedule_action, a template "Schedule post action" is exposed as ../publishpress-hub/mcp/future/schedule-post-action. The tool arguments are the template params. Calling the tool copies the template into a new workflow with those params filled, and the engine runs that workflow.

Predefined tools can stay. Templates are an additional, optional source of tools. The same template is used for manual "new workflow from template" and for MCP. The param form in the editor is the same input list the MCP tool schema uses.

Behavior

• Mark a template as an MCP tool (optional, off by default).
• Tool name and description come from the template.
• Tool input schema comes from the template params.
• A tool call creates a new workflow from the template and executes that workflow. It does not execute the template itself.
• Registration is done by this plugin. Hub is the MCP server that exposes what this plugin registers.

Out of scope

Template storage, the Templates menu, the editor, and the param form belong to #1720.