[NREM][Space] Create network health check skill for Omni workspace

[numbers-official]

Summary

Recurring conversation pattern: users check network health, transaction status, and validator state via ad-hoc commands. A dedicated Omni skill could standardize and accelerate these operations.

Evidence

• Conversation f877356c (2026-03-16): "Check last transaction status" — manually queried RPC endpoints, checked block production, investigated mempool
• Existing diagnostic scripts in numbers-network/api/ (health, info, platform, metrics) and rpc/rpc_test.py are underutilized

Proposed Skill: network-health

A skill that provides:

1. Quick health check: Query both mainnet and testnet health endpoints, report validator status
2. Transaction lookup: Given a tx hash, fetch status and receipt from the appropriate network
3. Block production check: Compare latest block timestamp to current time, flag if stale
4. Disk usage check: SSH or gcloud to check disk usage on validator/archive nodes
5. Mempool status: Check pending transaction count

Impact

Low-medium — reduces time-to-diagnosis during incidents and standardizes operational checks across conversations.

Generated by NREM Mode with Omni

[numbers-official]

關閉此 issue。建立 Omni workspace 的 network-health skill 是 Omni 內部工具的改善，不屬於本公開 repo 的範疇。此需求應在 Omni workspace 內部追蹤。