Fix some textures not being loaded to due being misaligned base64 data

src/main/java/moe/nea/firmament/mixins/TextureUnpackBase64PadPatch.java

@@ -0,0 +1,24 @@
+/*
+ * SPDX-FileCopyrightText: 2024 Linnea Gräf <nea@nea.moe>
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
+package moe.nea.firmament.mixins;
+
+import com.llamalad7.mixinextras.injector.ModifyExpressionValue;
+import com.mojang.authlib.yggdrasil.YggdrasilMinecraftSessionService;
+import moe.nea.firmament.util.Base64Util;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.injection.At;
+
+@Mixin(value = YggdrasilMinecraftSessionService.class, remap = false)
+public class TextureUnpackBase64PadPatch {
+    @ModifyExpressionValue(method = "unpackTextures",
+        remap = false,
+        at = @At(value = "INVOKE", target = "Lcom/mojang/authlib/properties/Property;value()Ljava/lang/String;"))
+    private String base64PadTexture(String original) {
+        if (original.length() % 4 == 0) return original;
+        return Base64Util.INSTANCE.padToValidBase64(original);
+    }
+}