IAMF upstream archive omissions

Only test/demo media fixtures and the precompiled web-demo WebAssembly binary were omitted.
All C/C++/Java source, BUILD files, .proto/.textproto files, configuration, scripts, and license notices are retained unchanged.
The omitted fixtures are not inputs to //iamf/include/iamf_tools:iamf_decoder_static.
Obtain full upstream data from the pinned source URL in SOURCE-MANIFEST.json to run upstream media-dependent tests or the web demo.

    11741025  iamf_tools/gh_pages/web_demo/data/Animated_demo_3OA.iamf
    12359428  iamf_tools/gh_pages/web_demo/data/Animated_demo_3OA_and_2_0.iamf
     7603305  iamf_tools/gh_pages/web_demo/data/videos/Animated_demo_720_silent.mp4
     3590019  iamf_tools/gh_pages/web_demo/decoder/wasm/wrapper.wasm
     5760044  iamf_tools/iamf/cli/testdata/Mechanism_5s.wav
     8640102  iamf_tools/iamf/cli/testdata/Mechanism_5s_24bit.wav
    11520044  iamf_tools/iamf/cli/testdata/Mechanism_5s_32bit.wav
     5292102  iamf_tools/iamf/cli/testdata/Mechanism_5s_44100hz_s16le.wav
     7680044  iamf_tools/iamf/cli/testdata/Transport_9.1.6_5s.wav
     9887440  iamf_tools/iamf/cli/testdata/Transport_TOA_5s.wav
      576080  iamf_tools/iamf/cli/testdata/audiolab-acoustic-guitar_2OA_470_ALLRAD_0.5s.wav
     5760078  iamf_tools/iamf/cli/testdata/audiolab-acoustic-guitar_2OA_470_ALLRAD_5s.wav
    26228814  iamf_tools/iamf/cli/testdata/audiolab-acoustic-guitar_2OA_470_ALLRAD_concat.wav
      965970  iamf_tools/iamf/cli/testdata/dialog_clip_stereo.wav
        2228  iamf_tools/iamf/cli/testdata/iamf/noise_1024samp_5p1_opus.iamf
        4293  iamf_tools/iamf/cli/testdata/iamf/noise_1024samp_stereo_flac.iamf
        2319  iamf_tools/iamf/cli/testdata/iamf/noise_3s_stereo_opus.iamf
        4715  iamf_tools/iamf/cli/testdata/iamf/tones_100ms_3OA_stereo_opus.iamf
        3188  iamf_tools/iamf/cli/testdata/iamf/tones_256samp_5p1_pcm.iamf
      384044  iamf_tools/iamf/cli/testdata/sample1_48kHz_stereo.wav
      192044  iamf_tools/iamf/cli/testdata/sawtooth_10000_foa_48khz.wav
       88278  iamf_tools/iamf/cli/testdata/sawtooth_10000_stereo_44100hz_s16le.wav
       96044  iamf_tools/iamf/cli/testdata/sawtooth_10000_stereo_48khz.wav
      144102  iamf_tools/iamf/cli/testdata/sawtooth_10000_stereo_48khz_s24le.wav
       32044  iamf_tools/iamf/cli/testdata/sawtooth_100_stereo.wav
      768044  iamf_tools/iamf/cli/testdata/sawtooth_8000_toa_48khz.wav
       32846  iamf_tools/iamf/cli/testdata/sine_1000_16khz_512ms.wav
       32812  iamf_tools/iamf/cli/testdata/sine_1000_16khz_512ms_s32le.wav
       96078  iamf_tools/iamf/cli/testdata/sine_1000_48khz.wav
       98382  iamf_tools/iamf/cli/testdata/sine_1000_48khz_512ms.wav
    12000102  iamf_tools/iamf/cli/testdata/sine_1000_4oa_48khz.wav
      480078  iamf_tools/iamf/cli/testdata/sine_1500_stereo_48khz_-15dBFS.wav
         110  iamf_tools/iamf/cli/testdata/stereo_8_samples_48khz_s16le.wav
         156  iamf_tools/iamf/cli/testdata/stereo_8_samples_48khz_s24le.wav
