fix: add mcp package.json and dep auto-install in install.sh

The MCP server requires @modelcontextprotocol/sdk and zod which are not
globally installed. Added .agents/mcp/package.json and updated install.sh
to run 'npm install --prefix' on first setup.

.agents/install.sh

@@ -121,6 +121,16 @@ for VSCODE_PROMPTS_DIR in \
   fi
 done
 
+# ── 7. MCP server dependencies ───────────────────────────────────────────────
+MCP_DIR="$DOTFILES_AGENTS/mcp"
+if [[ ! -d "$MCP_DIR/node_modules/@modelcontextprotocol" ]]; then
+  log "Installing MCP server dependencies (npm install in $MCP_DIR)..."
+  npm install --prefix "$MCP_DIR" --silent
+  log "MCP server dependencies installed"
+else
+  skip "MCP server node_modules already present"
+fi
+
 # ── Done ─────────────────────────────────────────────────────────────────────
 printf '\n\033[0;32minstall.sh complete.\033[0m\n'
 printf 'Next steps:\n'

.agents/mcp/package.json

@@ -0,0 +1,10 @@
+{
+  "name": "@dotfiles/all-agents-mcp",
+  "version": "1.0.0",
+  "private": true,
+  "type": "module",
+  "dependencies": {
+    "@modelcontextprotocol/sdk": "^1.29.0",
+    "zod": "^4.1.12"
+  }
+}