docs: link every client in the clients-page chooser + correctness sweep

The "Which should I use?" table on the clients page listed most client
names as bold text, not links — only the Decky plugin and pf-webos were
clickable — so the client references appeared broken. Link each client to
its section (or dedicated page), and fix a stale Windows headless command.

Repo-wide docs correctness/staleness pass against the code:
- steam-deck: client-not-found -> flatpak-not-found (the real backend code)
- install: host cert is punktfunk-host-windows_<ver>.cer, not ..._setup.cer
- configuration: GPU_PRIORITY_CLASS default is auto; 10BIT/444 are default-on
- how-it-works/index: GameStream/Moonlight is opt-in (--gamestream)
- roadmap: clipboard sync is shipped, not planned
- install-client: MSIX/cert artifacts are arch-suffixed (_x64/_arm64)
- requirements: fix garbled 22H2/IddCx sentence
- status: Linux encode also covers AMD/Intel (VAAPI/Vulkan Video)
- automation: add the plugins.changed event
- windows-host: note the optional bundled VB-CABLE virtual mic
- sway: PUNKTFUNK_COMPOSITOR=hyprland is a wlroots-family alias
- running-as-a-service: punktfunk-probe is a source-build-only dev tool

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

docs-site/content/docs/status.md

@@ -32,9 +32,9 @@ host is newer than the Linux host.)
 - **Native resolution, no scaling.** Every session gets a virtual display at the client's
   exact resolution and refresh rate, via per-compositor backends for **KWin**,
   **gamescope**, **Mutter**, and **Sway/wlroots**.
-- **Zero-copy GPU pipeline.** Captured frames stay on the GPU (dmabuf → CUDA → NVENC) with
-  automatic split-encode at very high resolutions. Stable 240 fps at 5120×1440 has been
-  measured. A GPU-less software H.264 encoder exists as an explicit fallback.
+- **Zero-copy GPU pipeline.** Captured frames stay on the GPU — dmabuf → CUDA → NVENC on NVIDIA, and
+  VAAPI or Vulkan Video on AMD/Intel — with automatic split-encode at very high resolutions. Stable
+  240 fps at 5120×1440 has been measured. A GPU-less software H.264 encoder exists as an explicit fallback.
 - **HDR (10-bit), on the Windows host.** An HDR Windows desktop is captured and encoded as HEVC
   Main10 (BT.2020 PQ) to HDR-capable clients (Windows, Android). Linux hosts stream 8-bit for now —
   HDR there is blocked upstream at the compositor.