Add DC Hub plugin (live data center, power and grid data via MCP)

[azmartone67]

📕 Read CONTRIBUTING.md first — it's the rulebook (every
field, the quality bar, the Awesome Score). Reviewers cite it by rule number (G1–G8, UC-n, PL-n).

What this adds

DC Hub, plugin (content/plugins/dc-hub.md): a hosted remote MCP server with live data-center, power, grid and fiber data for site selection.

Checklist

• This PR adds exactly ONE new file under content/ (plus assets for this entry, if any).
• It follows CONTRIBUTING.md — required fields + the golden rules (G1–G8).
• npm run validate passes locally (schema, slug, vocabularies).
• slug is kebab-case and exactly matches the filename.
• I ran / used this myself end to end — it works today.
• Every URL in the frontmatter resolves to real, relevant content.
• The prompt body is the real, complete prompt — not a summary or a teaser.
• The entry body is plain markdown — no raw HTML (<script>, <iframe>, <style>, <form>, inline event handlers). CI rejects it (§8.5).
• I did NOT set verified_at or status: live — a maintainer sets those during verification (§10.1).
• This is not an ad. A listing that exists to funnel traffic to your product gets closed. Sponsor slots will exist for that — this isn't one.
• If this is someone else's work: author is the original creator, the origin is linked (source_url for a plugin, source_tweets[] for a use case), and scouted_by is me. (n/a, I maintain DC Hub)
• If the source is a YouTube video: ... (n/a)
• I license this contribution under CC BY 4.0 (attribution: entry author + grokbot.dev).

Where it came from

I maintain DC Hub and run it from my own Grok Bot as a connector. Project: https://dchub.cloud · MCP endpoint: https://dchub.cloud/mcp (Streamable HTTP, free tier needs no key) · repo: https://github.com/azmartone67/dchub-mcp-server · also listed in the Official MCP Registry. Copy follows our canonical listing text; no prices or counts beyond the DCPI's 300+ markets. Happy to change anything you'd like.