refactor(client): extract UI-agnostic plumbing into pf-client-core (phase 0)

Session pump, FFmpeg decode, PipeWire audio, SDL3 gamepads, keymap, trust
store, mDNS discovery, library client and Wake-on-LAN move verbatim from
clients/linux into crates/pf-client-core, shared with the upcoming Vulkan
session binary (punktfunk-planning: linux-client-rearchitecture.md).
The GTK client re-exports them at the crate root so every existing
crate::-path keeps resolving; its manifest drops the moved-only deps.

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

Cargo.lock

@@ -2740,6 +2740,25 @@ version = "2.3.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9b4f627cb1b25917193a259e49bdad08f671f8d9708acfd5fe0a8c1455d87220"
 
+[[package]]
+name = "pf-client-core"
+version = "0.8.2"
+dependencies = [
+ "anyhow",
+ "async-channel",
+ "ffmpeg-next",
+ "mdns-sd",
+ "opus",
+ "pipewire",
+ "punktfunk-core",
+ "rustls",
+ "sdl3",
+ "serde",
+ "serde_json",
+ "tracing",
+ "ureq",
+]
+
 [[package]]
 name = "pf-driver-proto"
 version = "0.0.1"
@@ -2927,21 +2946,14 @@ version = "0.8.2"
 dependencies = [
  "anyhow",
  "async-channel",
- "ffmpeg-next",
  "gtk4",
  "khronos-egl",
  "libadwaita",
- "mdns-sd",
- "opus",
- "pipewire",
+ "pf-client-core",
  "punktfunk-core",
- "rustls",
- "sdl3",
- "serde",
  "serde_json",
  "tracing",
  "tracing-subscriber",
- "ureq",
 ]
 
 [[package]]

Cargo.toml

@@ -5,6 +5,7 @@ members = [
     "crates/punktfunk-host",
     "crates/punktfunk-host/vendor/usbip-sim",
     "crates/punktfunk-tray",
+    "crates/pf-client-core",
     "crates/pf-driver-proto",
     "clients/probe",
     "clients/linux",

clients/android/native/Cargo.toml

@@ -20,7 +20,7 @@ punktfunk-core = { path = "../../../crates/punktfunk-core", features = ["quic"]
 jni = "0.21"
 log = "0.4"
 # LAN host discovery: browse the host's `_punktfunk._udp` mDNS advert — the SAME crate + service the
-# Linux/Windows clients use (`clients/linux/src/discovery.rs`), replacing Android's per-OEM
+# Linux/Windows clients use (`crates/pf-client-core/src/discovery.rs`), replacing Android's per-OEM
 # `NsdManager` system daemon with one tested browse path. Pure Rust (socket2/if-addrs/mio), so it
 # cross-compiles to the Android targets AND builds on the host (the JNI seam links into
 # `cargo build --workspace`). Kotlin keeps only the Wi-Fi `MulticastLock` + permission UX.

clients/android/native/src/discovery.rs

@@ -1,5 +1,5 @@
 //! LAN host discovery over mDNS, in Rust via `mdns-sd` — the same crate + service type the
-//! Linux/Windows clients use (`clients/linux/src/discovery.rs`), exposed to Kotlin over JNI.
+//! Linux/Windows clients use (`crates/pf-client-core/src/discovery.rs`), exposed to Kotlin over JNI.
 //!
 //! Why not `NsdManager`: that API delegates to a per-OEM system mDNS daemon whose reliability
 //! varies wildly (the Android client's discovery was "mostly broken"). Browsing in our own Rust

clients/linux/Cargo.toml

@@ -15,6 +15,10 @@ path = "src/main.rs"
 # Everything is Linux-gated so `cargo build --workspace` stays green on macOS (the Mac
 # client lives in clients/apple); on other platforms this builds as a stub binary.
 [target.'cfg(target_os = "linux")'.dependencies]
+# Session pump, decode, audio, gamepads, trust, discovery, keymap — the UI-agnostic
+# plumbing, shared with the upcoming Vulkan session binary (design: punktfunk-planning
+# linux-client-rearchitecture.md). This crate keeps only the GTK shell + GL presenter.
+pf-client-core = { path = "../../crates/pf-client-core" }
 punktfunk-core = { path = "../../crates/punktfunk-core", features = ["quic"] }
 
 # UI shell. GraphicsOffload needs GTK ≥ 4.14; black-background ≥ 4.16. AlertDialog/
@@ -23,25 +27,10 @@ gtk = { package = "gtk4", version = "0.11", features = ["v4_16"] }
 adw = { package = "libadwaita", version = "0.9", features = ["v1_5"] }
 async-channel = "2"
 
-# Video decode (same FFmpeg pin as the host) and audio.
-ffmpeg-next = "8"
-opus = "0.3"
-pipewire = "0.9"
-
-# Gamepads: capture + feedback (full DualSense fidelity — touchpad/motion/triggers/LEDs
-# need the hidapi driver).
-sdl3 = { version = "0.18", features = ["hidapi"] }
 # The VAAPI GL presenter (video_gl.rs): EGL dmabuf import into a GDK-shared context, dlopened
 # at runtime (`dynamic`) so GPU-less boxes and the software path never touch libEGL.
 khronos-egl = { version = "6", features = ["dynamic"] }
 
-mdns-sd = "0.20"
-# Game-library fetch from the host's management API over mTLS + fingerprint pinning.
-# `ureq` is small + sync (the host uses it too) and its rustls unifies with the
-# workspace's (quinn's) 0.23; the pinning verifier mirrors core's private `PinVerify`.
-ureq = "2"
-rustls = { version = "0.23", features = ["ring"] }
-serde = { version = "1", features = ["derive"] }
 serde_json = "1"
 anyhow = "1"
 tracing = "0.1"

clients/linux/README.md

@@ -78,15 +78,15 @@ src/
   ui_trust.rs             TOFU / PIN-pairing / request-access dialogs
   ui_settings.rs          resolution · refresh · decoder · bitrate · compositor · mic
   ui_stream.rs            the stream window (GtkGraphicsOffload present) + input capture
-  launch.rs · session.rs  session launch/UI glue; lifecycle over the NativeClient connector
-  video.rs                FFmpeg VAAPI / software decode → dmabuf / texture
-  audio.rs                PipeWire playback + mic uplink
-  gamepad.rs · keymap.rs  SDL3 controllers + feedback; keyboard VK mapping
-  trust.rs · discovery.rs persistent identity, known hosts + settings, mDNS browse
-  library.rs              mgmt-API library client (mTLS + pinned fingerprint, art proxy)
+  launch.rs               session launch/UI glue over the shared session pump
+  video_gl.rs             VAAPI dmabuf → RGBA GL presenter (EGL import, CICP-driven CSC)
 tools/screenshots.sh      store screenshot capture (app self-capture; Xvfb fallback)
 ```
 
+The UI-agnostic plumbing — session pump, FFmpeg decode, PipeWire audio, SDL3 gamepads +
+keymap, trust store, mDNS discovery, library client, Wake-on-LAN — lives in
+`crates/pf-client-core`, shared with the Vulkan session binary.
+
 ## Related
 
 - **[Documentation](https://docs.punktfunk.unom.io)** — quick start, pairing, troubleshooting

clients/linux/src/main.rs

@@ -5,27 +5,19 @@
 //! mirrors the Apple client: persistent identity, TOFU prompt with the host fingerprint,
 //! SPAKE2 PIN pairing.
 
+// The UI-agnostic plumbing lives in `pf-client-core`, shared with the upcoming Vulkan
+// session binary (design: punktfunk-planning linux-client-rearchitecture.md, Phase 0).
+// Root re-exports keep every existing `crate::video`-style path resolving unchanged.
+#[cfg(target_os = "linux")]
+pub use pf_client_core::{audio, discovery, gamepad, keymap, library, session, trust, video, wol};
+
 #[cfg(target_os = "linux")]
 mod app;
 #[cfg(target_os = "linux")]
-mod audio;
-#[cfg(target_os = "linux")]
 mod cli;
 #[cfg(target_os = "linux")]
-mod discovery;
-#[cfg(target_os = "linux")]
-mod gamepad;
-#[cfg(target_os = "linux")]
-mod keymap;
-#[cfg(target_os = "linux")]
 mod launch;
 #[cfg(target_os = "linux")]
-mod library;
-#[cfg(target_os = "linux")]
-mod session;
-#[cfg(target_os = "linux")]
-mod trust;
-#[cfg(target_os = "linux")]
 mod ui_gamepad_library;
 #[cfg(target_os = "linux")]
 mod ui_hosts;
@@ -38,12 +30,8 @@ mod ui_stream;
 #[cfg(target_os = "linux")]
 mod ui_trust;
 #[cfg(target_os = "linux")]
-mod video;
-#[cfg(target_os = "linux")]
 mod video_gl;
 
-mod wol;
-
 #[cfg(target_os = "linux")]
 fn main() -> gtk::glib::ExitCode {
     app::run()

crates/pf-client-core/Cargo.toml

@@ -0,0 +1,36 @@
+[package]
+name = "pf-client-core"
+description = "Shared Linux-client plumbing — session pump, FFmpeg decode, PipeWire audio, SDL3 gamepads, trust store, discovery — extracted from the GTK client so the shell and the Vulkan session binary build on one implementation"
+version.workspace = true
+edition.workspace = true
+rust-version.workspace = true
+license.workspace = true
+authors.workspace = true
+repository.workspace = true
+
+# Same Linux gating as clients/linux: `cargo build --workspace` stays green on macOS
+# (the Mac client lives in clients/apple); elsewhere this crate is `wol` plus stubs-free
+# emptiness. `wol` is pure std and stays cross-platform, matching the old main.rs.
+[target.'cfg(target_os = "linux")'.dependencies]
+punktfunk-core = { path = "../punktfunk-core", features = ["quic"] }
+async-channel = "2"
+
+# Video decode (same FFmpeg pin as the host) and audio.
+ffmpeg-next = "8"
+opus = "0.3"
+pipewire = "0.9"
+
+# Gamepads: capture + feedback (full DualSense fidelity — touchpad/motion/triggers/LEDs
+# need the hidapi driver).
+sdl3 = { version = "0.18", features = ["hidapi"] }
+
+mdns-sd = "0.20"
+# Game-library fetch from the host's management API over mTLS + fingerprint pinning.
+# `ureq` is small + sync (the host uses it too) and its rustls unifies with the
+# workspace's (quinn's) 0.23; the pinning verifier mirrors core's private `PinVerify`.
+ureq = "2"
+rustls = { version = "0.23", features = ["ring"] }
+serde = { version = "1", features = ["derive"] }
+serde_json = "1"
+anyhow = "1"
+tracing = "0.1"

crates/pf-client-core/src/lib.rs

@@ -0,0 +1,26 @@
+//! Shared, UI-agnostic Linux-client plumbing, extracted verbatim from the GTK client
+//! (design: punktfunk-planning `linux-client-rearchitecture.md`, Phase 0) so the desktop
+//! shell and the Vulkan session binary build on one implementation.
+//!
+//! Nothing here may depend on a UI toolkit: the presenter contract is `session`'s
+//! channels (`SessionHandle`) and `video`'s `DecodedImage` (RGBA bytes or dmabuf fds +
+//! plane layout) — how frames reach the screen is the consumer's business.
+
+#[cfg(target_os = "linux")]
+pub mod audio;
+#[cfg(target_os = "linux")]
+pub mod discovery;
+#[cfg(target_os = "linux")]
+pub mod gamepad;
+#[cfg(target_os = "linux")]
+pub mod keymap;
+#[cfg(target_os = "linux")]
+pub mod library;
+#[cfg(target_os = "linux")]
+pub mod session;
+#[cfg(target_os = "linux")]
+pub mod trust;
+#[cfg(target_os = "linux")]
+pub mod video;
+
+pub mod wol;

crates/punktfunk-tray/Cargo.toml

@@ -23,7 +23,7 @@ anyhow = "1"
 serde = { version = "1", features = ["derive"] }
 serde_json = "1"
 # Loopback HTTPS poll of GET /api/v1/local/summary. Same sync ureq + rustls(ring) stack and
-# custom-verifier pattern as the Linux client's library fetch (clients/linux/src/library.rs) —
+# custom-verifier pattern as the Linux client's library fetch (crates/pf-client-core/src/library.rs) —
 # but ring-only (no default aws-lc-rs provider: it needs a C toolchain per target and the agent
 # pins the ring provider explicitly anyway).
 ureq = { version = "2", default-features = false, features = ["tls"] }