added Git Package Manager

src/PackageManager.h

@@ -0,0 +1,64 @@
+#pragma once
+
+#include "Common.h"
+#include "ScriptCompiler.h"
+#include <cctype>
+
+struct PackageInfo {
+    std::string id;
+    std::string name;
+    std::string description;
+    bool builtIn = false;
+    bool external = false;
+    std::string gitUrl;
+    fs::path localPath;     // Absolute path for external packages
+    fs::path includeHint;   // Absolute include root for external packages
+    std::vector<fs::path> includeDirs;
+    std::vector<std::string> defines;
+    std::vector<std::string> linuxLibs;
+    std::vector<std::string> windowsLibs;
+};
+
+// Minimal package manager for script dependencies. Keeps a small registry of
+// known/bundled packages and a per-project manifest of which optional ones are
+// enabled. Installed packages augment the script build config (include dirs,
+// defines, link libs) before compilation.
+class PackageManager {
+public:
+    PackageManager();
+
+    void setProjectRoot(const fs::path& root);
+    const std::vector<PackageInfo>& getRegistry() const { return registry; }
+    const std::vector<std::string>& getInstalled() const { return installedIds; }
+    bool isInstalled(const std::string& id) const;
+    bool install(const std::string& id);
+    bool installGitPackage(const std::string& url,
+                           const std::string& nameHint,
+                           const std::string& includeRel,
+                           std::string& outId);
+    bool checkGitStatus(const std::string& id, std::string& outStatus);
+    bool updateGitPackage(const std::string& id, std::string& outLog);
+    bool remove(const std::string& id);
+    void applyToBuildConfig(ScriptBuildConfig& config) const;
+    const std::string& getLastError() const { return lastError; }
+
+private:
+    void buildRegistry();
+    void loadManifest();
+    void saveManifest() const;
+    const PackageInfo* findPackage(const std::string& id) const;
+    bool isBuiltIn(const std::string& id) const;
+    static std::string trim(const std::string& value);
+    static std::string slugify(const std::string& value);
+    static bool runCommand(const std::string& command, std::string& output);
+    bool ensureProjectRoot() const;
+    std::vector<std::string> split(const std::string& input, char delim) const;
+    std::string join(const std::vector<std::string>& vals, char delim) const;
+    fs::path packagesFolder() const;
+
+    fs::path projectRoot;
+    fs::path manifestPath;
+    std::vector<PackageInfo> registry;
+    std::vector<std::string> installedIds;
+    std::string lastError;
+};