Add orchestration script for audio recording E2E test

Builds host injector + device binary, injects 440Hz via gRPC,
runs capture+verify on emulator, reports PASS/FAIL.

Author: xaionaro@dx.center

tests/e2e/run-audio-e2e.sh

@@ -0,0 +1,88 @@
+#!/usr/bin/env bash
+# E2E test: inject audio via gRPC and verify capture on Android emulator.
+#
+# Prerequisites:
+#   - Android NDK installed (auto-detected or set ANDROID_NDK_HOME)
+#   - A running Android emulator with audio enabled (no -no-audio flag)
+#   - Emulator gRPC port accessible (default: console_port + 3000)
+#
+# Usage: ./tests/e2e/run-audio-e2e.sh
+
+set -euo pipefail
+
+SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
+PROJECT_DIR="$(cd "$SCRIPT_DIR/../.." && pwd)"
+
+# Detect NDK.
+ANDROID_HOME="${ANDROID_HOME:-$HOME/Android/Sdk}"
+NDK_PATH="${ANDROID_NDK_HOME:-$(ls -d "$ANDROID_HOME/ndk/"* 2>/dev/null | sort -V | tail -1)}"
+if [ -z "$NDK_PATH" ] || [ ! -d "$NDK_PATH" ]; then
+    echo "ERROR: Android NDK not found; set ANDROID_NDK_HOME or ANDROID_HOME"
+    exit 1
+fi
+
+API_LEVEL="${API_LEVEL:-35}"
+CC="${NDK_PATH}/toolchains/llvm/prebuilt/linux-x86_64/bin/x86_64-linux-android${API_LEVEL}-clang"
+if [ ! -x "$CC" ]; then
+    echo "ERROR: NDK clang not found at $CC"
+    exit 1
+fi
+
+ADB="${ADB:-adb}"
+
+# Verify adb connectivity.
+if ! "$ADB" get-state >/dev/null 2>&1; then
+    echo "ERROR: No adb device found. Start an emulator first."
+    exit 1
+fi
+
+# Determine gRPC port from emulator serial (e.g. emulator-5554 → 8554).
+if [ -z "${GRPC_PORT:-}" ]; then
+    SERIAL=$("$ADB" get-serialno 2>/dev/null | tr -d '\r\n')
+    if [[ "$SERIAL" =~ emulator-([0-9]+) ]]; then
+        CONSOLE_PORT="${BASH_REMATCH[1]}"
+        GRPC_PORT=$((CONSOLE_PORT + 3000))
+    else
+        GRPC_PORT=8554
+    fi
+fi
+echo "Using gRPC port: $GRPC_PORT"
+
+cd "$PROJECT_DIR"
+
+# Step 1: Build host-side injector.
+echo "=== Building audio injector (host) ==="
+go build -o /tmp/audio-inject ./tests/e2e/audio-inject
+
+# Step 2: Cross-compile device binary.
+echo "=== Building audio recording E2E (android/amd64) ==="
+CGO_ENABLED=1 GOOS=android GOARCH=amd64 CC="$CC" \
+    go build -o /tmp/audio-recording-e2e ./tests/e2e/audio-recording-e2e
+
+# Step 3: Start injector in background (440 Hz, 5 seconds).
+echo "=== Starting audio injection (440 Hz @ 48 kHz, 5s) ==="
+/tmp/audio-inject -port "$GRPC_PORT" -freq 440 -duration 5s &
+INJECT_PID=$!
+trap "kill $INJECT_PID 2>/dev/null || true; rm -f /tmp/audio-inject /tmp/audio-recording-e2e" EXIT
+
+# Give the injector time to connect and start streaming.
+sleep 2
+
+# Step 4: Push and run device binary.
+echo "=== Running audio recording E2E on device ==="
+"$ADB" push /tmp/audio-recording-e2e /data/local/tmp/audio-recording-e2e >/dev/null 2>&1
+"$ADB" shell chmod 755 /data/local/tmp/audio-recording-e2e
+
+OUTPUT=$("$ADB" shell "timeout 15 /data/local/tmp/audio-recording-e2e 2>&1; echo EXIT=\$?" 2>&1)
+echo "$OUTPUT"
+
+EXIT_CODE=$(echo "$OUTPUT" | grep -oP 'EXIT=\K\d+' | tail -1)
+"$ADB" shell rm -f /data/local/tmp/audio-recording-e2e 2>/dev/null || true
+
+if [ "$EXIT_CODE" = "0" ]; then
+    echo "=== PASS: Audio recording E2E ==="
+else
+    echo "=== FAIL: Audio recording E2E (exit=$EXIT_CODE) ==="
+fi
+
+exit "${EXIT_CODE:-1}"