test runner, cross-target runners, lib/exe split

- subprocess-isolated test runner (replaces V1 dlopen-RunTest);
  Pass/Fail/Crash/Timeout/Skipped outcomes via :Test partition
- TestRunner abstraction with command templates: Local, Ssh,
  SshWin (cmd.exe-shell), QemuUser, FromEnv; probe-based skip
  when runner unreachable
- transitive PCM-path propagation in Build(); resolveImport
  walks deps recursively; depResults cache keyed by PcmDir()
  so per-target builds don't collide
- cfg.sysroot threaded through BuildStdPcm + base compile/link
  command (enables aarch64 cross via Arch Linux ARM rootfs)
- lib + exe split: project.cpp defines crafterBuildLib
  (LibraryStatic) + crafterBuildExe (Executable depending on
  it); build.sh produces lib/libcrafter-build.a alongside
  bin/crafter-build for downstream static-link consumers
- Windows DLL+launcher: CRAFTER_API macro, /EXPORT flag for
  project.dll's CrafterBuildProject; Crafter::Run as the real
  entry point with main.cpp as a thin wrapper
- 18 tests: HelloWorld/WithModule/Defines/CrossProjectModule/
  Diamond × (Linux + sshwin:winvm), plus Incremental,
  BuildError, Libraries, RunnerClassification, QemuUser,
  SshRunner, WindowsViaSsh, CrossArchAarch64
- single ./bin/crafter-build test runs everything; Windows
  variants skip gracefully if winvm SSH alias unreachable

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

interfaces/Crafter.Build-Test.cppm

@@ -0,0 +1,46 @@
+/*
+Crafter® Build
+Copyright (C) 2026 Catcrafts®
+Catcrafts.net
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License version 3.0 as published by the Free Software Foundation;
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301 USA
+*/
+
+module;
+#include "Crafter.Build-Api.h"
+export module Crafter.Build:Test;
+import std;
+import :Clang;
+
+export namespace Crafter {
+    struct RunTestsOptions {
+        std::vector<std::string> globs;
+        int jobs = 0;
+        std::optional<std::chrono::seconds> timeoutOverride;
+        bool listOnly = false;
+    };
+
+    struct TestSummary {
+        int passed = 0;
+        int failed = 0;
+        int crashed = 0;
+        int timedOut = 0;
+        int skipped = 0;
+        std::vector<TestResult> results;
+        bool AllPassed() const { return failed == 0 && crashed == 0 && timedOut == 0; }
+    };
+
+    CRAFTER_API TestSummary RunTests(Configuration& projectCfg, const RunTestsOptions& opts);
+    CRAFTER_API TestResult RunSingleTest(const Test& test, const std::filesystem::path& binary, std::chrono::seconds timeout);
+}