🔨 Support "hot-delete" of scripting files from the cache

[zach2good]

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Describe the feature

Inside filewatcher.cpp we only handle modifying files:

// cppcheck-suppress passedByValue
void Filewatcher::handleFileAction(efsw::WatchID watchid, std::string const& dir, std::string const& filename, efsw::Action action, std::string oldFilename)
{
    TracySetThreadName("Filewatcher Thread");
    TracyZoneScoped;
    std::filesystem::path fullPath = dir + "/" + filename;
    switch (action)
    {
        case efsw::Actions::Add:
            break;
        case efsw::Actions::Delete:
            break;
        case efsw::Actions::Modified:
            modifiedQueue.enqueue(fullPath);
            break;
        case efsw::Actions::Moved:
            break;
        default:
            break;
    }
}

luautils.cpp:

    void ReloadFilewatchList()
    {
        std::set<std::string> filenames; // For de-duping

        std::filesystem::path path;
        while (filewatcher->modifiedQueue.try_dequeue(path))
        {
            if (path.extension() == ".lua")
            {
                std::string filename = path.relative_path().generic_string();
                filenames.insert(filename);
            }
        }

        for (auto const& filename : filenames)
        {
            ShowInfo("[FileWatcher] %s", filename);
            CacheLuaObjectFromFile(filename, true);
        }
    }

We need to do something like:

modifiedQueue.enqueue({ fullPath, actionType(MODIFY/DELETE/WHATEVER) });

and then handle it on the other end (on the main thread) and wipe things from the cache if the relevant file was deleted

[zach2good]

This will also need "debouncing" of the filewatcher event. The OS might deliver signals of a file being modified after it was deleted, so it needs to catch that sort of thing safely.