feat(plugin/ruview): wire @ruvnet/rvagent MCP server (plugin v0.3.0)

Registers @ruvnet/rvagent 0.1.0 as an MCP server in plugin.json, so
installing the ruview plugin auto-exposes bfld_last_scan, bfld_subscribe,
presence_now, vitals_get_breathing, vitals_get_heart_rate, vitals_get_all,
and vitals_fetch as first-class Claude Code tool calls instead of shell-out
via the ruview-rvagent skill.

Updates the ruview-rvagent skill + Codex prompt with a Quickstart section
covering the published npm package and the RVAGENT_SENSING_URL override.
The existing Rust-crate exploration content (vendor/ruvector/crates/rvAgent)
remains as the substrate for deeper RVF-aware agentic flows.

Co-Authored-By: claude-flow <ruv@ruv.net>

plugins/ruview/codex/prompts/ruview-rvagent.md

@@ -2,6 +2,24 @@
 
 You are helping the operator explore or prototype the integration of `vendor/ruvector/crates/rvAgent/` (a production Rust AI-agent framework) with RuView's existing sensing pipeline (`v2/crates/wifi-densepose-*`) and the RVF cognitive container format (`v2/crates/wifi-densepose-sensing-server/src/rvf_container.rs`).
 
+## Live MCP server: `@ruvnet/rvagent` v0.1.0
+
+The TypeScript MCP server (`tools/ruview-mcp/`, published as `@ruvnet/rvagent`) is live on npm and exposes `bfld_last_scan`, `bfld_subscribe`, `presence_now`, `vitals_get_breathing`, `vitals_get_heart_rate`, `vitals_get_all`, `vitals_fetch`. Add to a Codex MCP config:
+
+```json
+{
+  "mcpServers": {
+    "rvagent": {
+      "command": "npx",
+      "args": ["-y", "@ruvnet/rvagent"],
+      "env": { "RVAGENT_SENSING_URL": "http://localhost:3000" }
+    }
+  }
+}
+```
+
+This is the operator-facing tool surface; the Rust crate below remains the substrate for deeper RVF-aware agentic flows.
+
 ## Trigger phrasing
 
 - "wire rvAgent into RuView"