transcoder_ffmpeg: fix memleak of encoder fmtCtx and filter_graph

builder/create_gif_page: add progress bar

transcoder_ffmpeg: fix memleak of filter_frame and filter_ctx

cd: fix the action-gh-release can't find layer file

Update LICENSE to GPL 2

release: update version to v1.5.4

transcoder_bmf: fix possible buffer overflow

transcoder_bmf: catch unexecpted exit with reminding

fix wrong encoder in output file by transcoder_bmf

Support AI feature on macOS (#137)

build: add logo for linglong build

release: update version to 1.5.3

feat: add minimal AI processing support (#133)

transcoder: fix abnormal progress bar display

transcoder_fftool: add cutting, qscale, pix_fmt, scale set