docs(changelog): update changelogs for 6.4.0

Signed-off-by: k4yt3x <[email protected]>

docs(readme): update readme for 6.3.1

Signed-off-by: k4yt3x <[email protected]>

fix(video2x): remove redundant newline statements

Signed-off-by: k4yt3x <[email protected]>

docs(*): update changelog and readme for 6.2.0

Signed-off-by: k4yt3x <[email protected]>

chore(release): bump version to 6.1.1

Signed-off-by: k4yt3x <[email protected]>

ci(release): disabled Ubuntu 24.04 build in the release pipeline

Signed-off-by: k4yt3x <[email protected]>

chore(librealesrgan): updated librealesrgan submodule path

Signed-off-by: k4yt3x <[email protected]>

fix(realesrgan): fixed incorrect type for ncnn::Mat elemsize

Signed-off-by: k4yt3x <[email protected]>

feat(*): updated Dockerfile and PKGBUILD for 6.0.0-beta.4

Signed-off-by: k4yt3x <[email protected]>

feat(*): switched to spdlog for logging and organized headers (k4yt3x…

…#1183)

* feat: updated PKGBUILD description
* feat: updated workflow syntax and dependencies
* feat: switched logging to spdlog
* chore: adjusted library defaults
* ci: fixed spdlog format string issues
* docs: fixed docs for libvideo2x functions
* feat: organized header files
* fix: fixed header installation directory
* feat: link spdlog statically if compiled from source
* feat: adjusted libvideo2x log level enum names
* feat: added version.h header

Signed-off-by: k4yt3x <[email protected]>