feat: promote linux native audio path

docs/release/linux-build.md

@@ -0,0 +1,91 @@
+# Chanora Linux build notes
+
+This document covers the current Linux desktop build and packaging flow for
+`apps/chanora_flutter`.
+
+## Prerequisites
+
+- Linux host with desktop Flutter support enabled
+- Rust stable
+- Flutter stable on `PATH`
+- CMake 3.13+
+- `pkg-config`
+- GTK3 development headers
+- Opus development headers that expose the `opus` pkg-config module used by
+  tsclientlib/audiopus for Linux audio encode/decode
+- PipeWire development headers that expose the `libpipewire-0.3` and
+  `libspa-0.2` pkg-config modules used by the primary Linux voice backend
+- PulseAudio development headers for the fallback Linux voice backend
+- `clang` and `gcc`
+- sibling checkout of `oboe-rs` at `../oboe-rs`
+
+Install `opus-devel` on Fedora-style hosts or `libopus-dev` on Debian/Ubuntu.
+The workspace does not vendor or patch Opus for Linux; the normal Linux build
+links the system `libopus` through `pkg-config`.
+
+For Linux audio specifically, the product uses PipeWire directly as the primary
+backend and PulseAudio directly as the fallback. If you want a fast preflight,
+these are the package checks that matter:
+
+```bash
+pkg-config --modversion gtk+-3.0
+pkg-config --modversion opus
+pkg-config --modversion libpipewire-0.3
+pkg-config --modversion libspa-0.2
+pkg-config --modversion libpulse
+pkg-config --modversion libpulse-simple
+```
+
+Use `libpipewire-0.3`, not `pipewire-0.3`. The latter probe will fail even on a
+correctly provisioned host because it is not the module name exported by the
+PipeWire development package.
+
+## Optional: bundle ONNX Runtime
+
+If you want the Linux bundle to include ONNX Runtime for Silero VAD, export:
+
+```bash
+export CHANORA_ONNXRUNTIME_SHARED_LIB=/absolute/path/to/libonnxruntime.so
+```
+
+When set, the Flutter Linux bundle will include:
+
+```text
+build/linux/x64/<mode>/bundle/lib/libonnxruntime.so
+```
+
+and the Linux runner will set `ORT_DYLIB_PATH` to that bundled file at app
+startup when the variable is not already present.
+
+## Build helper
+
+From the repository root:
+
+```bash
+./tools/build-linux.sh
+```
+
+The Flutter Linux CMake bundle now owns staging `libchanora_bridge.so` into
+`bundle/lib/`. A plain `flutter build linux` will build the host-profile Rust
+bridge automatically; `tools/build-linux.sh` exports
+`CHANORA_BRIDGE_SHARED_LIB` so release bundles use the already-built targeted
+artifact instead of duplicating the copy logic in shell.
+
+Useful variants:
+
+```bash
+./tools/build-linux.sh --no-rust
+./tools/build-linux.sh --regenerate-bindings
+./tools/build-linux.sh --version v0.2.0-beta.1
+```
+
+## Debian package helper
+
+To build a `.deb` package:
+
+```bash
+./tools/build-linux-deb.sh
+```
+
+If `CHANORA_ONNXRUNTIME_SHARED_LIB` is set, the Debian helper now verifies that
+`libonnxruntime.so` was actually bundled before packaging.