Move the asset tools under soh/assets

soh-torch and soh-o2r-packer both exist to turn assets into archives, so
they sit better beside the assets they read than at the repo root.

Nothing tangled: both targets are declared in the root CMakeLists with
explicit paths rather than add_subdirectory, and soh/CMakeLists.txt globs
only include/, soh/ and src/, so sources under assets/ aren't swept into
the soh target.

soh/assets/tools/torch-cli/main.cpp

@@ -0,0 +1,110 @@
+// Build-time ROM extraction, for the ExtractAssets target and anything else that needs an
+// archive without launching the game.
+//
+// soh links torch as a static library (USE_STANDALONE=OFF), which compiles out torch's own
+// CLI, so this supplies the entry point. It calls the same SohTorch::Extract the game does.
+
+#include <algorithm>
+#include <cstdio>
+#include <cstdlib>
+#include <filesystem>
+#include <string>
+#include <vector>
+
+#include "TorchExtract.h"
+
+namespace fs = std::filesystem;
+
+static void Usage(const char* argv0) {
+    fprintf(stderr, "usage: %s --src <asset yml dir> --dest <output dir> --version <M.m.p> <rom|dir> [rom|dir...]\n",
+            argv0);
+}
+
+static bool IsRom(const fs::path& path) {
+    const std::string ext = path.extension().string();
+    return ext == ".z64" || ext == ".n64" || ext == ".v64";
+}
+
+// A directory argument extracts every rom directly inside it, which is how the target is
+// normally driven: drop a vanilla and a master quest rom in, get oot.o2r and oot-mq.o2r.
+static std::vector<std::string> CollectRoms(const std::vector<std::string>& args) {
+    std::vector<std::string> roms;
+
+    for (const auto& arg : args) {
+        std::error_code ec;
+        if (fs::is_directory(arg, ec)) {
+            std::vector<std::string> found;
+            for (fs::directory_iterator it(arg, ec), end; it != end; it.increment(ec)) {
+                if (ec) {
+                    break;
+                }
+                if (it->is_regular_file(ec) && IsRom(it->path())) {
+                    found.push_back(it->path().string());
+                }
+            }
+            std::sort(found.begin(), found.end());
+            roms.insert(roms.end(), found.begin(), found.end());
+        } else {
+            roms.push_back(arg);
+        }
+    }
+
+    return roms;
+}
+
+int main(int argc, char** argv) {
+    std::string src, dest, version;
+    std::vector<std::string> romArgs;
+
+    for (int i = 1; i < argc; i++) {
+        const std::string arg = argv[i];
+        auto next = [&](const char* what) -> std::string {
+            if (i + 1 >= argc) {
+                fprintf(stderr, "missing argument after %s\n", what);
+                exit(1);
+            }
+            return argv[++i];
+        };
+
+        if (arg == "--src") {
+            src = next("--src");
+        } else if (arg == "--dest") {
+            dest = next("--dest");
+        } else if (arg == "--version") {
+            version = next("--version");
+        } else if (!arg.empty() && arg[0] == '-') {
+            fprintf(stderr, "unknown option: %s\n", arg.c_str());
+            Usage(argv[0]);
+            return 1;
+        } else {
+            romArgs.push_back(arg);
+        }
+    }
+
+    if (src.empty() || dest.empty() || version.empty() || romArgs.empty()) {
+        Usage(argv[0]);
+        return 1;
+    }
+
+    const std::vector<std::string> roms = CollectRoms(romArgs);
+    if (roms.empty()) {
+        fprintf(stderr, "no roms found in: ");
+        for (const auto& arg : romArgs) {
+            fprintf(stderr, "%s ", arg.c_str());
+        }
+        fprintf(stderr, "\n");
+        return 1;
+    }
+
+    for (const auto& rom : roms) {
+        // A fresh extraction per ROM; torch names the archive from config.yml.
+        const std::string archive = SohTorch::Extract(rom, src, dest, version, nullptr);
+        if (archive.empty()) {
+            fprintf(stderr, "failed to extract %s\n", rom.c_str());
+            return 1;
+        }
+        printf("%s -> %s/%s\n", rom.c_str(), dest.c_str(), archive.c_str());
+    }
+
+    return 0;
+}