fix: address PR redhat-developer#45 review feedback

- Bump version to 0.6.0 (rebase on main which is at 0.5.0)
- Remove @ prefix from backstage-upgrade in routing table
- Add dependency note for cross-skill version reference
- Add cross-references between NFS guide and skill references

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: rohitkrai03

README.md

@@ -26,11 +26,7 @@ Build dynamic plugins from scratch — backend or frontend — and get them depl
 
 Migrate your plugins from the legacy Backstage frontend system to the New Frontend System (NFS).
 
-Start with the **[NFS Migration Guide](./docs/nfs-migration-guide.md)** -- it covers what NFS is, why you need to migrate, the deprecation timeline, and walks through every migration pattern with code examples.
-
-When you're ready to migrate, use the Agent Skill to automate it:
-
-- **[nfs-migration](./skills/nfs-migration/SKILL.md)** -- Analyzes your existing plugin, applies the right Blueprint patterns, updates exports, and verifies the result. Two approaches: direct-to-GA (recommended) or phased with backward compatibility.
+- **[nfs-migration](./skills/nfs-migration/SKILL.md)** -- Analyzes your existing plugin, applies the right Blueprint patterns, updates exports, and verifies the result. Two approaches: direct-to-GA (recommended) or phased with backward compatibility. Reference files cover every extension type, mount point mapping, operator config, gotchas, and verification.
 
 ### Backstage Upgrade