docs: restructure host setup by distro, configuration by compositor

Split the docs' single distro×desktop axis (ubuntu-gnome / ubuntu-kde / fedora-kde) into two,
which deduplicates the shared mechanics and scales to distros that run several desktops (Arch):

- Install the host — per distro/OS (ubuntu, fedora, arch, bazzite, steamos-host, windows-host):
  GPU driver + package + input group, then a canonical "Configure your desktop" funnel.
- Configure your desktop — per compositor (kde, gnome, gamescope, sway): host.env, compositor
  quirks, the headless session, and starting the host.

New shared web-console page (enable · login password · arm pairing) removes the console/password
block that was copy-pasted across all seven host pages. Merged ubuntu-gnome + ubuntu-kde into
ubuntu; renamed fedora-kde to fedora; kept bazzite and steamos-host as dedicated appliance guides
(trimmed of duplication). Moved the KWin headless session, the GNOME EGL/lock traps, and the
gamescope attach/managed model out of the distro pages onto their compositor pages.

Fixed while restructuring: distro-specific paths on kde (kde-desktop-setup.sh is Fedora/Bazzite-only;
the .deb ships host.env.kde under /usr/share/punktfunk-host), the interactive "start the host" step
that was lost in the merge, sway over-claiming Hyprland, and a pre-existing broken anchor in
how-it-works.

Removal of the three old pages was captured by the preceding commit 8ebb614 (a concurrent commit
swept up the staged git-rm); the net docs tree is correct. Fumadocs build + internal link/anchor
check green.

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

docs-site/content/docs/install.md

@@ -16,9 +16,9 @@ On **Windows**, the host ships as a signed installer instead — see [Windows](#
 
 | Distro | Package manager | One-command happy path | Guide |
 |--------|-----------------|------------------------|-------|
-| **Ubuntu / Debian** | apt | `sudo apt install punktfunk-host` | [Ubuntu — GNOME](/docs/ubuntu-gnome) · [Ubuntu — KDE](/docs/ubuntu-kde) · [packaging/debian](https://git.unom.io/unom/punktfunk/src/branch/main/packaging/debian/README.md) |
+| **Ubuntu / Debian** | apt | `sudo apt install punktfunk-host` | [Ubuntu / Debian](/docs/ubuntu) · [packaging/debian](https://git.unom.io/unom/punktfunk/src/branch/main/packaging/debian/README.md) |
 | **Bazzite / Fedora Atomic** | systemd-sysext | `sudo bash punktfunk-sysext.sh install` (no layering, no reboot) | [Bazzite](/docs/bazzite) · [packaging/bazzite](https://git.unom.io/unom/punktfunk/src/branch/main/packaging/bazzite/README.md) |
-| **Fedora (dnf)** | dnf / rpm-ostree | `dnf install punktfunk punktfunk-web` | [Fedora — KDE](/docs/fedora-kde) · [packaging/rpm](https://git.unom.io/unom/punktfunk/src/branch/main/packaging/rpm/README.md) |
+| **Fedora (dnf)** | dnf / rpm-ostree | `dnf install punktfunk punktfunk-web` | [Fedora](/docs/fedora) · [packaging/rpm](https://git.unom.io/unom/punktfunk/src/branch/main/packaging/rpm/README.md) |
 | **Arch** | pacman | `pacman -Sy punktfunk-host` (binary repo) | [Arch Linux](/docs/arch) · [packaging/arch](https://git.unom.io/unom/punktfunk/src/branch/main/packaging/arch/README.md) |
 | **SteamOS (host)** | on-device script | `bash scripts/steamdeck/install.sh` | [SteamOS (Host)](/docs/steamos-host) |
 
@@ -79,13 +79,22 @@ fallback without one. More detail — including the CLI `punktfunk-host service
    Bare `serve` is the secure native-only default (native `punktfunk/1` + the web console). On a
    trusted LAN, add `--gamestream` to also serve stock [Moonlight](/docs/moonlight) clients.
 
-3. Enable the web console and read its login password, then open `http://<host-ip>:47992`:
+3. Enable the web console:
 
    ```sh
    systemctl --user enable --now punktfunk-web
-   journalctl --user -u punktfunk-web-init | sed -n 's/.*password generated: //p'
    ```
 
+   Then open `http://<host-ip>:47992`. Reading its [login password](/docs/web-console#login-password)
+   and [arming PIN pairing](/docs/web-console#arm-pairing) are covered in
+   [The Web Console](/docs/web-console).
+
+### Configure your desktop
+
+How the virtual display and input work depends on your desktop — see [KDE](/docs/kde),
+[GNOME](/docs/gnome), [Steam / gamescope](/docs/gamescope), or [Sway](/docs/sway) for the
+compositor-specific setup.
+
 From there, follow the [Quick Start](/docs/quickstart) to pair your first client. To run the host
 automatically at boot, see [Running as a Service](/docs/running-as-a-service).