Submit WordPress Studio MCP listing to Windsurf/Cascade marketplace

Parent: #45

## Goal
Determine and submit the WordPress Studio MCP server listing for Windsurf / Cascade / Devin Desktop.

## Evidence
- Official docs: https://docs.devin.ai/desktop/cascade/mcp.md
- Devin Desktop / Cascade documents an MCP Marketplace, official MCP entries, deeplinks, and team registry controls.
- Generated output: `plugins/windsurf/`.

## Tasks
- Confirm whether the listing should be the WordPress Studio MCP server rather than the repo-local Windsurf output.
- Gather listing metadata, install instructions, icons/screenshots if required, and MCP config details.
- Submit to the marketplace/listing path or file the required upstream request.
- Record the submission URL/status back in #45.

Start with the official Devin Desktop/Cascade MCP marketplace documentation linked in the issue, then inspect the generated plugins/windsurf/ output and parent issue #45. Done means determining the correct WordPress Studio MCP listing, gathering required metadata, install instructions, config details, and any assets, submitting or filing the upstream request, and recording its URL/status in #45.

Written by the indexing model from the issue text.