Export audio clip

Fixes an issue with the audio preview generator using the wrong sample rate when clipping the audio which is resulting in incorrect exported audio files. Allows referencing and playing back audio clips and now generalizes the behavior as AssetFile(s).

Diffs=
a69bfba11 Export audio clip (#6949)

Co-authored-by: Luigi Rosso <luigi-rosso@users.noreply.github.com>

.rive_head

diff --git a/.rive_head b/.rive_head
index 292ff7c..34c1fdd 100644
--- a/.rive_head
+++ b/.rive_head
@@ -1 +1 @@
-fee67f16df7648b5c9bc100b6221c7ba5baca0af
+a69bfba11ec4a116b8712af0b685aa27a5309e43

src/audio/audio_reader.cpp

diff --git a/src/audio/audio_reader.cpp b/src/audio/audio_reader.cpp
index bfc3d18..8451b3c 100644
--- a/src/audio/audio_reader.cpp
+++ b/src/audio/audio_reader.cpp
@@ -12,7 +12,7 @@
 AudioReader::~AudioReader() { ma_decoder_uninit(&m_decoder); }
 
 uint32_t AudioReader::channels() const { return m_channels; }
-uint32_t AudioReader::sampleRate() const { return m_source->sampleRate(); }
+uint32_t AudioReader::sampleRate() const { return m_decoder.outputSampleRate; }
 ma_decoder* AudioReader::decoder() { return &m_decoder; }
 
 uint64_t AudioReader::lengthInFrames()