container: root: macros: add Pluggable support

- Adds requirements to support auto-(un)load'ing, refactors

- Adds loader argument to unit tests and benchmarks
  * Filters can now be passed as a loader argument

- Adds loader argument to Hash macro
  * Factored out from shell caller

container/src/root/macro/test/benchmark.C

@@ -1,6 +1,6 @@
 // docker-finance | modern accounting for the power-user
 //
-// Copyright (C) 2021-2025 Aaron Fiore (Founder, Evergreen Crypto LLC)
+// Copyright (C) 2021-2026 Aaron Fiore (Founder, Evergreen Crypto LLC)
 //
 // This program is free software: you can redistribute it and/or modify
 // it under the terms of the GNU General Public License as published by
@@ -61,27 +61,61 @@ class Benchmark
 
  public:
   //! \brief Macro for running all benchmarks
-  //! \todo parameter arg that takes list of benchmarks
-  static void run()
+  static void run() { ::benchmark::RunSpecifiedBenchmarks(); }
+
+ public:
+  static constexpr std::initializer_list<std::string_view> m_paths{
+      {"test/benchmark/hash.hh"},
+      {"test/benchmark/random.hh"},
+      {"test/benchmark/utility.hh"}};
+};
+
+//! \brief Pluggable entrypoint
+//! \ingroup cpp_macro_impl
+//! \since docker-finance 1.1.0
+class benchmark_C final
+{
+ public:
+  benchmark_C() = default;
+  ~benchmark_C() = default;
+
+  benchmark_C(const benchmark_C&) = default;
+  benchmark_C& operator=(const benchmark_C&) = default;
+
+  benchmark_C(benchmark_C&&) = default;
+  benchmark_C& operator=(benchmark_C&&) = default;
+
+ public:
+  //! \brief Macro auto-loader
+  //! \param arg Optional code to execute after loading
+  static void load(const std::string& arg = {})
   {
-    static bool loaded{false};
-    static const std::initializer_list<std::string> paths{
-        {"test/benchmark/hash.hh"},
-        {"test/benchmark/random.hh"},
-        {"test/benchmark/utility.hh"}};
+    for (auto path : Benchmark::m_paths)
+      ::dfi::common::load(std::string{path});
 
-    if (!loaded)
-      {
-        ::dfi::common::Command::load(paths);
-        loaded = true;
-      }
-
-    // TODO(unassigned): add argc,argv to macro/function signatures
     static int argc{1};
     static const char* argv{"docker-finance"};
     ::benchmark::Initialize(&argc, const_cast<char**>(&argv));
-    ::benchmark::RunSpecifiedBenchmarks();
+
+    // NOTE: benchmark filters can only be set via environment
+    // (when calling this macro via `dfi` `root`, as an argument)
+    Benchmark::run();
+
+    if (!arg.empty())
+      ::dfi::common::line(arg);
+  }
+
+  //! \brief Macro auto-unloader
+  //! \param arg Optional code to execute before unloading
+  static void unload(const std::string& arg = {})
+  {
+    if (!arg.empty())
+      ::dfi::common::line(arg);
+
     ::benchmark::Shutdown();
+
+    for (auto path : Benchmark::m_paths)
+      ::dfi::common::unload(std::string{path});
   }
 };
 }  // namespace test