Don't compress images sent through the Files attachment picker (#6755)

* Don't compress images sent through the Files attachment picker

Images and videos picked through the "Attachment" picker are now
uploaded without re-encoding, regardless of the "Optimize media quality"
setting. The gallery and camera pickers keep the existing behaviour,
matching what Element Web/Desktop and most other messengers do.

Fixes #6365

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

* Make sure we select the right video preset for sending as file

Wait for the video size estimations to be calculated before preprocessing the video file

---------

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
Co-authored-by: Jorge Martín <jorgem@element.io>

libraries/mediaupload/test/src/main/kotlin/io/element/android/libraries/mediaupload/test/FakeMediaPreProcessor.kt

@@ -31,6 +31,10 @@ class FakeMediaPreProcessor(
     var cleanUpCallCount = 0
         private set
 
+    /** The [MediaOptimizationConfig] passed to the most recent [process] call, or `null` if it was never called. */
+    var lastMediaOptimizationConfig: MediaOptimizationConfig? = null
+        private set
+
     private var result: Result<MediaUploadInfo> = Result.success(
         MediaUploadInfo.AnyFile(
             File("test"),
@@ -51,6 +55,7 @@ class FakeMediaPreProcessor(
     ): Result<MediaUploadInfo> = simulateLongTask {
         processLatch?.await()
         processCallCount++
+        lastMediaOptimizationConfig = mediaOptimizationConfig
         result
     }