fix: When sending media as files use the application/octet-stream mime type (#4815)

This ensures there is no media pre-processing applied, but also has the side effect of not sending a thumbnail as we (incorrectly) did until now.

Author: jmartinesp

features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/messagecomposer/MessageComposerPresenter.kt

@@ -24,7 +24,6 @@ import androidx.compose.runtime.rememberUpdatedState
 import androidx.compose.runtime.saveable.rememberSaveable
 import androidx.compose.runtime.setValue
 import androidx.compose.runtime.snapshots.SnapshotStateList
-import androidx.media3.common.MimeTypes
 import androidx.media3.common.util.UnstableApi
 import dagger.assisted.Assisted
 import dagger.assisted.AssistedFactory
@@ -42,6 +41,7 @@ import io.element.android.features.messages.impl.timeline.TimelineController
 import io.element.android.features.messages.impl.utils.TextPillificationHelper
 import io.element.android.libraries.architecture.Presenter
 import io.element.android.libraries.core.extensions.runCatchingExceptions
+import io.element.android.libraries.core.mimetype.MimeTypes
 import io.element.android.libraries.designsystem.utils.snackbar.SnackbarDispatcher
 import io.element.android.libraries.designsystem.utils.snackbar.SnackbarMessage
 import io.element.android.libraries.featureflag.api.FeatureFlagService
@@ -166,13 +166,13 @@ class MessageComposerPresenter @AssistedInject constructor(
             handlePickedMedia(uri, mimeType)
         }
         val filesPicker = mediaPickerProvider.registerFilePicker(AnyMimeTypes) { uri ->
-            handlePickedMedia(uri)
+            handlePickedMedia(uri, MimeTypes.OctetStream)
         }
         val cameraPhotoPicker = mediaPickerProvider.registerCameraPhotoPicker { uri ->
-            handlePickedMedia(uri, MimeTypes.IMAGE_JPEG)
+            handlePickedMedia(uri, MimeTypes.Jpeg)
         }
         val cameraVideoPicker = mediaPickerProvider.registerCameraVideoPicker { uri ->
-            handlePickedMedia(uri, MimeTypes.VIDEO_MP4)
+            handlePickedMedia(uri, MimeTypes.Mp4)
         }
         val isFullScreen = rememberSaveable {
             mutableStateOf(false)