Initial commit: WilloW-PMTools marketplace with willow-pmtools plugin

Marketplace with one plugin (willow-pmtools) that wires the projecttodos
MCP server (mcp.willowbrook.work) into Cowork and ships a /todos morning
briefing slash command.

.claude-plugin/marketplace.json

@@ -0,0 +1,16 @@
+{
+  "$schema": "https://json.schemastore.org/claude-code-plugin-marketplace.json",
+  "name": "willow-pm-marketplace",
+  "displayName": "Willowbrook PM Tools",
+  "description": "Internal Willowbrook plugins for project management — todos, lists, and other PM workflows wired up to the company's 4D backend.",
+  "owner": {
+    "name": "Willowbrook",
+    "url": "https://willowbrook.build"
+  },
+  "plugins": [
+    {
+      "name": "willow-pmtools",
+      "source": "./plugins/willow-pmtools"
+    }
+  ]
+}