feat(storage): add storage governance and metadata management

[2362787603]

Summary

• Add storage quota/governance APIs, LLM-backed decision settings, and storage metadata index management.
• Add frontend admin storage governance/index/compare pages and related API clients.
• Make Ceph toolbox access self-heal by auto-mounting CephFS in the existing Rook toolbox when needed.

Testing

• make pre-commit-check in backend
• go test ./pkg/storagegovernance ./pkg/llm ./pkg/storageindex ./pkg/cronjob ./internal/handler
• frontend pre-commit checks and manual deployment test