feat(decky): visible branded Steam shortcut, one-tap client updates, fullscreen-page polish

- The "Punktfunk" shortcut is no longer hidden: it now ships committed
  artwork (grid/wide/hero/logo/icon, generated by scripts/gen-steam-art.py
  — a pure-stdlib SDF renderer drawing the lens mark + a monoline
  "punktfunk" wordmark) applied via SetCustomArtworkForApp /
  SetShortcutIcon. Existing installs are unhidden and re-arted once per
  ART_VERSION; relaunching the library entry streams to the last host.
- Updates cover the flatpak CLIENT too: check_update compares the
  user-scope installed commit against its remote, applyUpdate runs
  `flatpak update --user` first (awaited) and the plugin reinstall —
  which reloads the panel — last; docs spell out the sudo-less --user
  update ("sudo flatpak update" silently skips per-user installs).
- Fullscreen page: DialogButton stretches to 100% width in the gamepad
  UI, so the Stream/Pair/Refresh/… actions filled whole rows — sized to
  content + right-aligned now; the header drops its Update button (About
  tab + QAM banner keep the flow) and the back button gets a real 40px
  hit target.
- Settings: the disable-Steam-Input note also shows for Automatic — on a
  Deck that now forwards the built-in controller as a Steam Deck pad
  (paddles/trackpads/gyro), which needs Steam Input off for the shortcut.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

docs-site/content/docs/install-client.md

@@ -34,10 +34,11 @@ flatpak install --user https://flatpak.unom.io/io.unom.Punktfunk.flatpakref
 flatpak run io.unom.Punktfunk
 ```
 
-Updates, from then on:
+Updates, from then on — **without `sudo`** (this is a `--user` install; `sudo flatpak update` only
+touches the *system* scope and silently skips it):
 
 ```sh
-flatpak update                       # or: flatpak update io.unom.Punktfunk
+flatpak update                       # or: flatpak update --user io.unom.Punktfunk
 ```
 
 Prefer your native package manager? The client also ships as real packages (add the repo once —

docs-site/content/docs/steam-deck.md

@@ -62,28 +62,38 @@ page (host list + stream settings).
 - **Pair** — for a locked host, [arm pairing on the host](/docs/pairing) (its console or web
   console shows a 4-digit PIN), then enter that PIN on the Deck's keypad. Pairing persists, so the
   next connection is silent.
-- **Stream** — pick a host and the stream launches fullscreen in Gaming Mode (as a hidden Steam
-  shortcut, so gamescope focuses it).
+- **Stream** — pick a host and the stream launches fullscreen in Gaming Mode (as a "Punktfunk"
+  Steam shortcut, so gamescope focuses it — it shows up in your library with its own artwork, and
+  relaunching it from there streams to the last host).
 - **Settings** — resolution, refresh, bitrate, gamepad type, and mic, written to the client the
-  plugin launches. Leave **Resolution** / **Refresh** on *Native* to get the Deck's own mode.
+  plugin launches. Leave **Resolution** / **Refresh** on *Native* to get the Deck's own mode. With
+  **Gamepad type** on *Automatic* the Deck's built-in controller is forwarded as a **Steam Deck**
+  pad (paddles, both trackpads, gyro) — that needs Steam Input set to **Off** for Punktfunk (game
+  page → ⚙ → Controller Settings), else Steam keeps those controls and only sticks + buttons reach
+  the host.
 
-To **leave a stream**: the in-client controller chord **L1 + R1 + Start + Select**, or close the
-"game" from the Steam overlay. Exiting the client ends the Steam game and drops you back to Gaming
-Mode.
+To **leave a stream**: **hold L1 + R1 + Start + Select** for about two seconds, or close the
+"game" from the Steam overlay. Either ends the session and drops you straight back to Gaming Mode.
 
 ## Updating
 
-The plugin **checks for updates itself** — no Decky store needed. When a newer build is available it
-shows an **Update to vX** button (in the Quick Access Menu panel and on the full page). Tap it,
-confirm Decky's prompt, and the plugin downloads, verifies, replaces itself, and reloads — without
-leaving Gaming Mode.
+The plugin **checks for updates itself** — no Decky store needed. It covers **both** the plugin *and*
+the streaming client (they version independently), so when either has a newer build the panel shows an
+**Update** button (in the Quick Access Menu and on the full page). Tap it: the client updates in
+place, and if the plugin itself changed it downloads, verifies, replaces itself, and reloads — all
+without leaving Gaming Mode.
 
-The check follows the [channel](/docs/channels) you installed from: a plugin installed from the
+The plugin check follows the [channel](/docs/channels) you installed from: a plugin installed from the
 **stable** link tracks stable releases; one installed from the **canary** link tracks `main` builds.
 
-> If the **Update** button never appears (an older Decky Loader, or no network), update manually:
-> Decky → **Developer** → **Install Plugin from URL**, and paste the same channel link again. Decky
-> replaces the installed copy in place.
+> **Updating the client from the terminal?** The client is a **per-user** Flatpak, so run
+> `flatpak update --user io.unom.Punktfunk` — **without `sudo`**. `sudo flatpak update` only touches
+> the *system* installation and silently skips the client. (Un-sudo'd `flatpak update` updates both
+> scopes, so it's the safe default.)
+
+> If the plugin **Update** button never appears (an older Decky Loader, or no network), update the
+> plugin manually: Decky → **Developer** → **Install Plugin from URL**, and paste the same channel
+> link again. Decky replaces the installed copy in place.
 
 ## Troubleshooting