Fixed some crashes in response strings source generator, reorganized more submodules into their folders

src/NadekoBot/Modules/Nsfw/_Common/Downloaders/KonachanImageDownloader.cs

@@ -0,0 +1,27 @@
+#nullable disable
+using System.Net.Http.Json;
+
+namespace NadekoBot.Modules.Nsfw.Common;
+
+public sealed class KonachanImageDownloader : ImageDownloader<DapiImageObject>
+{
+    private readonly string _baseUrl;
+
+    public KonachanImageDownloader(HttpClient http)
+        : base(Booru.Konachan, http)
+        => _baseUrl = "https://konachan.com";
+
+    public override async Task<List<DapiImageObject>> DownloadImagesAsync(
+        string[] tags,
+        int page,
+        bool isExplicit = false,
+        CancellationToken cancel = default)
+    {
+        var tagString = ImageDownloaderHelper.GetTagString(tags, isExplicit);
+        var uri = $"{_baseUrl}/post.json?s=post&q=index&limit=200&tags={tagString}&page={page}";
+        var imageObjects = await _http.GetFromJsonAsync<DapiImageObject[]>(uri, _serializerOptions, cancel);
+        if (imageObjects is null)
+            return new();
+        return imageObjects.Where(x => x.FileUrl is not null).ToList();
+    }
+}