docs: user-facing docs revamp — structured product docs + per-platform setup

Replace the dev/agent-log pages with a proper user-facing doc set:

- Getting Started: Introduction (rewritten), How It Works, Quick Start.
- Host Setup: Requirements, then clean per-platform guides — Ubuntu GNOME,
  Ubuntu KDE, Fedora KDE (new), Bazzite (rewritten) — plus Running as a Service
  (desktop / headless GNOME / headless KDE).
- Connecting: Clients overview, Moonlight, Pairing & Trust.
- Configuration: host.env reference, Host CLI, Troubleshooting.
- The dev/design notes (architecture, roadmap, the deferred design specs, CI)
  move to a clearly-separated "Project & Internals" nav section.

Removes the superseded box-specific pages (gnome-box, headless-box, linux-setup,
overview). status.md (the internal progress tracker, with box IPs) is kept as a
file but dropped from the public nav. Site builds clean.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

docs-site/content/docs/quickstart.md

@@ -0,0 +1,54 @@
+---
+title: Quick Start
+description: From nothing to streaming — set up a host and connect your first client.
+---
+
+This is the shortest path to a working stream. Each step links to the details.
+
+## 1. Set up the host
+
+On your Linux + NVIDIA machine, follow the guide for your system:
+
+- [Ubuntu — GNOME](/docs/ubuntu-gnome)
+- [Ubuntu — KDE Plasma](/docs/ubuntu-kde)
+- [Fedora — KDE Plasma](/docs/fedora-kde)
+- [Bazzite — gamescope / Steam](/docs/bazzite)
+
+Each one covers the NVIDIA driver, the dependencies, and how to build and run the host. Check the
+[Requirements](/docs/requirements) first if you're not sure your machine is a fit.
+
+## 2. Start the host
+
+From a terminal **inside your desktop session** (so the host can reach your compositor):
+
+```sh
+punktfunk-host serve --native
+```
+
+The host starts listening and prints its identity fingerprint. It advertises itself on your local
+network, so clients can find it by name. Leave it running. (To start it automatically at boot, see
+[Running as a Service](/docs/running-as-a-service).)
+
+## 3. Connect and pair a client
+
+On the device you want to stream to:
+
+- **Apple (Mac, iPhone, iPad, Apple TV):** open the punktfunk app — your host appears under *On this
+  network*. Tap it, and when prompted, **pair**.
+- **Anything with Moonlight:** add the host (it should be discovered automatically), then pair.
+
+To pair, the host needs to show a PIN. Arm pairing from the host's web console (or with
+`--allow-pairing` on the command line) — the host displays a 4-digit PIN, you type it into the client,
+and they trust each other from then on. Full details: [Pairing & Trust](/docs/pairing).
+
+## 4. Stream
+
+Once paired, select the host and start streaming. The host creates a virtual display at your device's
+resolution and refresh, and the picture comes up. Mouse, keyboard, and controllers flow back to the
+host.
+
+## Next steps
+
+- Tune [resolution, refresh, and bitrate](/docs/configuration).
+- Run the host [as a background service](/docs/running-as-a-service) so it's always available.
+- Hit a snag? See [Troubleshooting](/docs/troubleshooting).