Add private location capabilities overview page (draft for review)

[newrelicsaurabh]

What & why

New Relic's private location capabilities are powerful but currently spread across many install and configuration pages, which makes them hard to discover. This adds a single Private location capabilities overview page that consolidates them, grouped by problem area:

• Foundation — deploy anywhere (Docker/Podman/Kubernetes/OpenShift), outbound-only, per-check sandboxing
• Security & hardening — custom CA certificates, non-root execution, verified script execution (VSE), secure credentials
• Compliance — FedRAMP Moderate (in scope)
• Networking — dual stack (IPv4 + IPv6), outbound proxy
• Extensibility — custom Node modules, user-defined variables
• Scaling & operations — heavyweight/lightweight workers, horizontal/vertical scaling, health events, queue purge, key rotation
• Automation — NerdGraph API + Terraform, shared locations

It also includes a capability matrix and a Not supported section clarifying that Kerberos auth and custom hostnames / /etc/hosts are not private-location features (a common misconception). Adds a sidenav entry under Private locations.

Draft — for review

This is a draft to solicit review and contribution. The page intentionally contains a "Draft for review" banner and a Contribution and open questions section (both marked to be removed before publishing).

Open questions for reviewers:

• RBAC capability names for managing private locations / secure credentials — need a source-of-truth confirmation.
• Runtime versions — the runtime-transition guide and install page differ on the target Chrome minor (146 vs 147); reconcile before quoting.
• Scope — should this also cover monitor-downtime / SJM maintenance, or just link out?
• Placement — currently added under Private locations, after the overview. Confirm this is the right home.

All technical claims are sourced from existing docs.newrelic.com pages; cross-links point to the canonical install/config pages.

🤖 Generated with Claude Code

[github-actions]

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