fix(parakeet-cpp): darwin/metal support (libparakeet.dylib + DYLD path)

The parakeet-cpp backend had no macOS support and panicked at startup on
Apple/Metal nodes when purego.Dlopen could not find "libparakeet.so".
Fix it across the same four layers the sibling voxtral backend already
handles correctly:

- main.go: default the dlopen target to libparakeet.dylib on darwin
  (runtime.GOOS), libparakeet.so elsewhere; PARAKEET_LIBRARY still wins.
- Makefile: also stage the built libparakeet.dylib next to the Go sources.
- package.sh: accept either the Linux .so[.X.Y] or the macOS .dylib when
  bundling instead of hard-failing when no .so is present (the macOS case);
  note that on Darwin only system frameworks are linked.
- run.sh: on Darwin set DYLD_LIBRARY_PATH and PARAKEET_LIBRARY to the
  packaged .dylib; keep LD_LIBRARY_PATH + .so on Linux.

Mirrors backend/go/voxtral.

Assisted-by: Claude:claude-opus-4-8
Signed-off-by: Ettore Di Giacinto <mudler@localai.io>

backend/go/parakeet-cpp/Makefile

@@ -74,6 +74,7 @@ libparakeet.so: sources/parakeet.cpp
 	cmake -B sources/parakeet.cpp/build-shared -S sources/parakeet.cpp $(CMAKE_ARGS)
 	cmake --build sources/parakeet.cpp/build-shared --config Release -j$(JOBS)
 	cp -fv sources/parakeet.cpp/build-shared/libparakeet.so* ./ 2>/dev/null || true
+	cp -fv sources/parakeet.cpp/build-shared/libparakeet.dylib ./ 2>/dev/null || true
 	cp -fv sources/parakeet.cpp/include/parakeet_capi.h ./
 
 parakeet-cpp-grpc: libparakeet.so main.go goparakeetcpp.go

backend/go/parakeet-cpp/main.go

@@ -2,15 +2,17 @@ package main
 
 // Started internally by LocalAI - one gRPC server per loaded model.
 //
-// Loads libparakeet.so via purego and registers the flat C-API entry
-// points declared in parakeet_capi.h. The library name can be overridden
-// with PARAKEET_LIBRARY (mirrors the WHISPER_LIBRARY / VIBEVOICECPP_LIBRARY
-// convention in the sibling backends); the default looks for the .so next
-// to this binary.
+// Loads the parakeet shared library via purego and registers the flat
+// C-API entry points declared in parakeet_capi.h. The library name can be
+// overridden with PARAKEET_LIBRARY (mirrors the WHISPER_LIBRARY /
+// VIBEVOICECPP_LIBRARY convention in the sibling backends); the default
+// looks next to this binary for libparakeet.so on Linux and
+// libparakeet.dylib on macOS.
 import (
 	"flag"
 	"fmt"
 	"os"
+	"runtime"
 
 	"github.com/ebitengine/purego"
 	grpc "github.com/mudler/LocalAI/pkg/grpc"
@@ -28,7 +30,11 @@ type LibFuncs struct {
 func main() {
 	libName := os.Getenv("PARAKEET_LIBRARY")
 	if libName == "" {
-		libName = "libparakeet.so"
+		if runtime.GOOS == "darwin" {
+			libName = "libparakeet.dylib"
+		} else {
+			libName = "libparakeet.so"
+		}
 	}
 
 	lib, err := purego.Dlopen(libName, purego.RTLD_NOW|purego.RTLD_GLOBAL)

backend/go/parakeet-cpp/package.sh

@@ -16,12 +16,15 @@ mkdir -p "$CURDIR/package/lib"
 cp -avf "$CURDIR/parakeet-cpp-grpc" "$CURDIR/package/"
 cp -avf "$CURDIR/run.sh" "$CURDIR/package/"
 
-# libparakeet.so + any soname symlinks (libparakeet.so.X[.Y]). purego.Dlopen
-# resolves it via LD_LIBRARY_PATH, which run.sh points at lib/.
-cp -avf "$CURDIR"/libparakeet.so* "$CURDIR/package/lib/" 2>/dev/null || {
-	echo "ERROR: libparakeet.so not found in $CURDIR, run 'make' first" >&2
+# libparakeet shared lib + any soname symlinks. On Linux this is
+# libparakeet.so[.X.Y]; on macOS it is libparakeet.dylib. purego.Dlopen
+# resolves it via the *_LIBRARY_PATH that run.sh points at lib/.
+cp -avf "$CURDIR"/libparakeet.so* "$CURDIR/package/lib/" 2>/dev/null || true
+cp -avf "$CURDIR"/libparakeet.dylib "$CURDIR/package/lib/" 2>/dev/null || true
+if ! ls "$CURDIR"/package/lib/libparakeet.* >/dev/null 2>&1; then
+	echo "ERROR: libparakeet shared library not found in $CURDIR, run 'make' first" >&2
 	exit 1
-}
+fi
 
 # Detect architecture and copy the core runtime libs libparakeet.so links
 # against, plus the matching dynamic loader as lib/ld.so.
@@ -48,7 +51,7 @@ elif [ -f "/lib/ld-linux-aarch64.so.1" ]; then
     cp -arfLv /lib/aarch64-linux-gnu/librt.so.1 "$CURDIR/package/lib/librt.so.1"
     cp -arfLv /lib/aarch64-linux-gnu/libpthread.so.0 "$CURDIR/package/lib/libpthread.so.0"
 elif [ "$(uname -s)" = "Darwin" ]; then
-    echo "Detected Darwin"
+    echo "Detected Darwin — system frameworks linked dynamically, no bundled libs needed"
 else
     echo "Error: Could not detect architecture"
     exit 1

backend/go/parakeet-cpp/run.sh

@@ -3,11 +3,17 @@ set -e
 
 CURDIR=$(dirname "$(realpath "$0")")
 
-export LD_LIBRARY_PATH="$CURDIR/lib:$CURDIR:${LD_LIBRARY_PATH:-}"
+if [ "$(uname)" = "Darwin" ]; then
+	export DYLD_LIBRARY_PATH="$CURDIR/lib:$CURDIR:${DYLD_LIBRARY_PATH:-}"
+	export PARAKEET_LIBRARY="$CURDIR/lib/libparakeet.dylib"
+else
+	export LD_LIBRARY_PATH="$CURDIR/lib:$CURDIR:${LD_LIBRARY_PATH:-}"
+	export PARAKEET_LIBRARY="$CURDIR/lib/libparakeet.so"
+fi
 
 # If a self-contained ld.so was packaged, route through it so the
 # packaged libc / libstdc++ are used instead of the host's (matches the
-# whisper backend's runtime layout).
+# whisper backend's runtime layout). Linux only.
 if [ -f "$CURDIR/lib/ld.so" ]; then
 	echo "Using lib/ld.so"
 	exec "$CURDIR/lib/ld.so" "$CURDIR/parakeet-cpp-grpc" "$@"