fix: add missing plugin declarations and fix hardcoded paths

- projman/plugin.json: Added commands, agents, and skills declarations
- project-hygiene/plugin.json: Added hooks declaration for PostToolUse
- projman/.mcp.json: Changed hardcoded paths to ${CLAUDE_PLUGIN_ROOT}
- cmdb-assistant/.mcp.json: Changed hardcoded paths to ${CLAUDE_PLUGIN_ROOT}

Plugins were not being recognized because plugin.json files only had
metadata but no component declarations.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

plugins/project-hygiene/.claude-plugin/plugin.json

@@ -8,5 +8,18 @@
   },
   "license": "MIT",
   "keywords": ["cleanup", "hygiene", "automation", "hooks", "maintenance"],
-  "repository": "https://github.com/bandit-labs/project-hygiene"
+  "repository": "https://github.com/bandit-labs/project-hygiene",
+  "hooks": {
+    "PostToolUse": [
+      {
+        "matcher": "Write|Edit",
+        "hooks": [
+          {
+            "type": "command",
+            "command": "${CLAUDE_PLUGIN_ROOT}/hooks/cleanup.sh"
+          }
+        ]
+      }
+    ]
+  }
 }