Ladybird/Android: Move host build into its own shell script

This lets us select a proper host compiler version if cc/cxx are not
suitable for building Lagom.

Ladybird/Android/BuildLagomTools.sh

@@ -0,0 +1,27 @@
+#!/usr/bin/env bash
+
+set -eo pipefail
+
+DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
+
+SERENITY_ROOT="$(realpath "${DIR}"/../..)"
+
+# shellcheck source=/dev/null
+. "${SERENITY_ROOT}/Meta/shell_include.sh"
+
+# shellcheck source=/dev/null
+. "${SERENITY_ROOT}/Meta/find_compiler.sh"
+
+pick_host_compiler
+
+BUILD_DIR=${BUILD_DIR:-"${SERENITY_ROOT}/Build"}
+CACHE_DIR=${CACHE_DIR:-"${BUILD_DIR}/caches"}
+
+cmake -S "$SERENITY_ROOT/Meta/Lagom" -B "$BUILD_DIR/lagom-tools" \
+    -GNinja -Dpackage=LagomTools \
+    -DCMAKE_INSTALL_PREFIX="$BUILD_DIR/lagom-tools-install"  \
+    -DCMAKE_C_COMPILER="$CC" \
+    -DCMAKE_CXX_COMPILER="$CXX" \
+    -DSERENITY_CACHE_DIR="$CACHE_DIR"
+
+ninja -C "$BUILD_DIR/lagom-tools" install