Reorganize: Move all skills to skills/ folder

- Created skills/ directory
- Moved 272 skills to skills/ subfolder
- Kept agents/ at root level
- Kept installation scripts and docs at root level

Repository structure:
- skills/           - All 272 skills from skills.sh
- agents/           - Agent definitions
- *.sh, *.ps1       - Installation scripts
- README.md, etc.   - Documentation

Co-Authored-By: Claude <noreply@anthropic.com>

skills/plugins/marketplaces/design-plugins/design-and-refine/hooks/hooks.json

@@ -0,0 +1,27 @@
+{
+  "description": "Check for leftover design lab files on session end",
+  "hooks": {
+    "SessionEnd": [
+      {
+        "hooks": [
+          {
+            "type": "command",
+            "command": "${CLAUDE_PLUGIN_ROOT}/scripts/cleanup-check.sh",
+            "timeout": 10
+          }
+        ]
+      }
+    ],
+    "Stop": [
+      {
+        "hooks": [
+          {
+            "type": "command",
+            "command": "${CLAUDE_PLUGIN_ROOT}/scripts/cleanup-check.sh",
+            "timeout": 10
+          }
+        ]
+      }
+    ]
+  }
+}