chore: Bump version to 0.22.0

Updated all component versions:
- bd CLI: 0.21.9 → 0.22.0
- Plugin: 0.21.9 → 0.22.0
- MCP server: 0.21.9 → 0.22.0
- npm package: 0.21.9 → 0.22.0
- Documentation: 0.21.9 → 0.22.0

Generated by scripts/bump-version.sh

.claude-plugin/marketplace.json

@@ -9,7 +9,7 @@
       "name": "beads",
       "source": "./",
       "description": "AI-supervised issue tracker for coding workflows",
-      "version": "0.21.9"
+      "version": "0.22.0"
     }
   ]
 }