Checkpoint 2: integrate native Editor, MCP, gameplay builds and standalone export

include/faset/core/process.hpp

@@ -0,0 +1,38 @@
+#pragma once
+#include <filesystem>
+#include <map>
+#include <memory>
+#include <optional>
+#include <string>
+#include <vector>
+
+namespace faset {
+struct ProcessOptions {
+    // First element is the executable. Arguments are passed directly, never through a shell.
+    std::vector<std::string> arguments;
+    std::filesystem::path working_directory;
+    std::map<std::string, std::string> environment;
+};
+struct ProcessPoll {
+    bool running{};
+    std::optional<int> exit_code;
+    std::string output; // Newly available stdout and stderr, combined.
+};
+class Process {
+  public:
+    explicit Process(const ProcessOptions&);
+    ~Process();
+    Process(Process&&) noexcept;
+    Process& operator=(Process&&) noexcept;
+    Process(const Process&) = delete;
+    Process& operator=(const Process&) = delete;
+    ProcessPoll poll();
+    // Terminates the process group/job, including its compiler children.
+    void cancel();
+
+  private:
+    struct Impl;
+    std::unique_ptr<Impl> impl_;
+};
+std::filesystem::path find_executable(const std::string& name);
+} // namespace faset