Fix PNG animations.

Adds an `InputStreamFactory` APNG decoder so images animate correctly when loaded via the new `DecryptableUriStreamLoader`.

app/src/main/java/org/thoughtcrime/securesms/glide/cache/ApngStreamFactoryDecoder.kt

@@ -0,0 +1,44 @@
+/*
+ * Copyright 2025 Signal Messenger, LLC
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+package org.thoughtcrime.securesms.glide.cache
+
+import com.bumptech.glide.load.Options
+import com.bumptech.glide.load.ResourceDecoder
+import com.bumptech.glide.load.engine.Resource
+import org.signal.core.util.StreamUtil
+import org.signal.glide.apng.decode.APNGDecoder
+import org.signal.glide.apng.decode.APNGParser
+import org.signal.glide.common.io.StreamReader
+import org.thoughtcrime.securesms.glide.GlideStreamConfig
+import org.thoughtcrime.securesms.mms.InputStreamFactory
+import java.nio.ByteBuffer
+
+/**
+ * A variant of [ApngStreamCacheDecoder] that decodes animated PNGs from [org.thoughtcrime.securesms.mms.InputStreamFactory] sources.
+ */
+class ApngStreamFactoryDecoder(
+  private val byteBufferDecoder: ResourceDecoder<ByteBuffer, APNGDecoder>
+) : ResourceDecoder<InputStreamFactory, APNGDecoder> {
+
+  override fun handles(source: InputStreamFactory, options: Options): Boolean {
+    return if (options.get(ApngOptions.ANIMATE) == true) {
+      return APNGParser.isAPNG(LimitedReader(StreamReader(source.create()), GlideStreamConfig.markReadLimitBytes))
+    } else {
+      false
+    }
+  }
+
+  override fun decode(
+    source: InputStreamFactory,
+    width: Int,
+    height: Int,
+    options: Options
+  ): Resource<APNGDecoder>? {
+    val data = StreamUtil.readFully(source.create())
+    val byteBuffer = ByteBuffer.wrap(data)
+    return byteBufferDecoder.decode(byteBuffer, width, height, options)
+  }
+}