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>

clients/decky/main.py

@@ -25,6 +25,7 @@ advert in ``crates/punktfunk-host/src/discovery.rs``.
 """
 
 import asyncio
+import base64
 import json
 import os
 import shutil
@@ -224,6 +225,71 @@ def _flatpak_env() -> dict:
     return env
 
 
+async def _flatpak_capture(args: list[str], timeout: float = 20.0) -> tuple[int, str]:
+    """Run ``flatpak <args>`` with the user-session env, merging stderr into stdout. Returns
+    ``(returncode, output)``; ``(-1, "")`` if the binary is missing or the call errors/times out.
+    Best-effort by design — every caller here treats a failure as "no update / can't tell"."""
+    flatpak = _flatpak()
+    if not flatpak:
+        return -1, ""
+    proc = None
+    try:
+        proc = await asyncio.create_subprocess_exec(
+            flatpak, *args,
+            stdout=asyncio.subprocess.PIPE, stderr=asyncio.subprocess.STDOUT,
+            env=_flatpak_env(),
+        )
+        out, _ = await asyncio.wait_for(proc.communicate(), timeout=timeout)
+        rc = proc.returncode if proc.returncode is not None else -1
+        return rc, (out or b"").decode("utf-8", "replace")
+    except asyncio.TimeoutError:
+        decky.logger.warning("flatpak %s timed out", " ".join(args))
+        if proc:
+            try:
+                proc.kill()
+            except ProcessLookupError:
+                pass
+        return -1, ""
+    except Exception:  # noqa: BLE001
+        decky.logger.exception("flatpak %s failed", " ".join(args))
+        return -1, ""
+
+
+def _field_from(text: str, name: str) -> str:
+    """Pull ``<name>: value`` out of ``flatpak info`` / ``remote-info`` output (e.g. ``Commit``,
+    ``Origin``)."""
+    prefix = f"{name}:"
+    for line in text.splitlines():
+        s = line.strip()
+        if s.startswith(prefix):
+            return s.split(":", 1)[1].strip()
+    return ""
+
+
+async def _client_update_state() -> dict:
+    """Is a newer commit of the flatpak client available in the remote it tracks? The client is a
+    **per-user** install (so ``sudo flatpak update``, which is system-scope, never touches it), and
+    it versions independently of this plugin — so we compare the installed commit against the
+    remote's here and let the QAM offer a user-scope update. Best-effort; all-``False`` on any error
+    (not installed, no flatpak, offline)."""
+    state = {"available": False, "installed": "", "remote": ""}
+    rc, info = await _flatpak_capture(["info", "--user", APP_ID], timeout=10.0)
+    if rc != 0:
+        return state  # client not installed as a user app / no flatpak
+    state["installed"] = _field_from(info, "Commit")
+    origin = _field_from(info, "Origin")
+    if not origin:
+        return state
+    rc, rinfo = await _flatpak_capture(["remote-info", "--user", origin, APP_ID], timeout=25.0)
+    if rc != 0:
+        return state  # remote unreachable — treat as "up to date", retry next check
+    state["remote"] = _field_from(rinfo, "Commit")
+    state["available"] = bool(
+        state["installed"] and state["remote"] and state["installed"] != state["remote"]
+    )
+    return state
+
+
 def _split_txt(txt: str) -> list[str]:
     """Split an avahi TXT column into tokens, honouring the ``"key=value"`` quoting."""
     tokens: list[str] = []
@@ -371,6 +437,27 @@ class Plugin:
         reason = (err.strip().splitlines() or out.strip().splitlines() or ["pairing failed"])[-1]
         return {"ok": False, "error": reason}
 
+    async def shortcut_art(self) -> dict:
+        """The Steam-shortcut artwork shipped with the plugin (``assets/``, generated by
+        ``scripts/gen-steam-art.py``): base64 PNGs for SetCustomArtworkForApp plus the
+        icon's absolute path for SetShortcutIcon (which wants a file, not bytes). Missing
+        files are simply omitted — artwork is cosmetic and must never block a launch."""
+        art: dict = {}
+        base = Path(decky.DECKY_PLUGIN_DIR) / "assets"
+        for key, fname in (
+            ("grid", "grid.png"),
+            ("gridwide", "gridwide.png"),
+            ("hero", "hero.png"),
+            ("logo", "logo.png"),
+        ):
+            try:
+                art[key] = base64.b64encode((base / fname).read_bytes()).decode()
+            except OSError:
+                pass
+        icon = base / "icon.png"
+        art["icon_path"] = str(icon) if icon.exists() else ""
+        return art
+
     async def runner_info(self) -> dict:
         """The wrapper-script path + flatpak app id the frontend needs to create the Steam
         shortcut. The shortcut invokes the script through ``/bin/sh`` (see steam.ts), so no
@@ -419,11 +506,37 @@ class Plugin:
             return {"ok": False}
         return {"ok": True}
 
+    async def update_client(self) -> dict:
+        """Update the flatpak **client** (io.unom.Punktfunk) in the USER installation — the scope a
+        Steam Deck install lives in, which ``sudo flatpak update`` (system-scope) never reaches.
+        Returns whether a new commit was actually pulled. Best-effort; non-fatal."""
+        flatpak = _flatpak()
+        if not flatpak:
+            return {"ok": False, "updated": False, "error": "flatpak-not-found"}
+        _, before = await _flatpak_capture(["info", "--user", APP_ID], timeout=10.0)
+        before_commit = _field_from(before, "Commit")
+        rc, out = await _flatpak_capture(["update", "--user", "-y", APP_ID], timeout=300.0)
+        if rc != 0:
+            decky.logger.warning("flatpak client update failed (rc=%s): %s", rc, out[-400:])
+            return {"ok": False, "updated": False, "error": "update-failed"}
+        _, after = await _flatpak_capture(["info", "--user", APP_ID], timeout=10.0)
+        after_commit = _field_from(after, "Commit")
+        updated = bool(before_commit and after_commit and before_commit != after_commit)
+        decky.logger.info(
+            "flatpak client update: %s -> %s (updated=%s)",
+            before_commit[:10], after_commit[:10], updated,
+        )
+        _update_cache["data"] = None  # invalidate the cached "update available" snapshot
+        return {"ok": True, "updated": updated}
+
     async def check_update(self, force: bool = False) -> dict:
-        """Is a newer build available in our registry? Compares the installed version
-        (``package.json``) against the per-channel ``manifest.json`` the CI publishes, and
-        returns everything the frontend needs to drive Decky's install RPC. Non-fatal: any
-        failure (no channel baked in, network down) returns ``update_available: False``.
+        """Report pending updates for BOTH the plugin and the flatpak client.
+
+        The plugin updates via Decky's install RPC (the per-channel ``manifest.json`` the CI
+        publishes); the **client** updates via ``flatpak update --user`` (a per-user install, so
+        ``sudo flatpak update`` — system-scope — never touches it) and versions independently, so
+        it's checked here too and applied through :meth:`update_client`. Non-fatal: any failure
+        leaves the respective ``*_update_available`` ``False``.
         """
         current = _installed_version()
         cfg = _update_config()
@@ -434,23 +547,37 @@ class Plugin:
             "hash": "",
             "channel": str(cfg.get("channel", "")),
             "update_available": False,
+            "client_update_available": False,
+            "client_current": "",
+            "client_latest": "",
         }
 
-        manifest_url = cfg.get("manifest")
-        if not manifest_url:
-            result["error"] = "update-channel-unknown"  # dev / sideloaded build
-            return result
-
         now = time.monotonic()
         cached = _update_cache["data"]
         if not force and cached and (now - _update_cache["at"]) < _UPDATE_TTL_S:
             return cached
 
+        # Client (flatpak) update — checked ALWAYS, even on a dev/sideloaded plugin build.
+        try:
+            cu = await _client_update_state()
+            result["client_update_available"] = bool(cu["available"])
+            result["client_current"] = (cu["installed"] or "")[:10]
+            result["client_latest"] = (cu["remote"] or "")[:10]
+        except Exception:  # noqa: BLE001
+            decky.logger.warning("client update check failed", exc_info=True)
+
+        manifest_url = cfg.get("manifest")
+        if not manifest_url:
+            result["error"] = "update-channel-unknown"  # dev / sideloaded plugin build
+            _update_cache["at"] = now
+            _update_cache["data"] = result  # the client info is still valid to cache
+            return result
+
         try:
             loop = asyncio.get_running_loop()
             manifest = await loop.run_in_executor(None, _fetch_json, manifest_url)
         except Exception as exc:  # noqa: BLE001
-            decky.logger.warning("update check failed: %s", exc)
+            decky.logger.warning("plugin update check failed: %s", exc)
             result["error"] = "fetch-failed"
             return result  # transient — don't cache, retry next open
 
@@ -461,8 +588,12 @@ class Plugin:
         result["update_available"] = bool(result["artifact"]) and (
             _semver_tuple(latest) > _semver_tuple(current)
         )
-        if result["update_available"]:
-            decky.logger.info("update available: %s -> %s (%s)", current, latest, result["channel"])
+        if result["update_available"] or result["client_update_available"]:
+            decky.logger.info(
+                "updates: plugin %s->%s (avail=%s), client->%s (avail=%s)",
+                current, latest, result["update_available"],
+                result["client_latest"], result["client_update_available"],
+            )
         _update_cache["at"] = now
         _update_cache["data"] = result
         return result